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Chiral and Catalytic Effects of Site-Specific Molecular Adsorption

  • Bogdana Borca*
    Bogdana Borca
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    National Institute of Materials Physics, Atomistilor 405A, 077125 Magurele, Ilfov, Romania
    *[email protected]
    More by Bogdana Borca
    Orcidhttps://orcid.org/0000-0001-5485-4536
  • , 
  • Tomasz Michnowicz
    Tomasz Michnowicz
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    More by Tomasz Michnowicz
  • , 
  • Fernando Aguilar-Galindo
    Fernando Aguilar-Galindo
    Donostia International Physics Center, E-20018 Donostia - San Sebastián, Spain
    More by Fernando Aguilar-Galindo
    Orcidhttps://orcid.org/0000-0003-2751-5592
  • , 
  • Rémi Pétuya
    Rémi Pétuya
    Donostia International Physics Center, E-20018 Donostia - San Sebastián, Spain
    More by Rémi Pétuya
    Orcidhttps://orcid.org/0000-0002-3118-6966
  • , 
  • Marcel Pristl
    Marcel Pristl
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    More by Marcel Pristl
  • , 
  • Verena Schendel
    Verena Schendel
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    More by Verena Schendel
  • , 
  • Ivan Pentegov
    Ivan Pentegov
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    More by Ivan Pentegov
  • , 
  • Ulrike Kraft
    Ulrike Kraft
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    Max Planck Institute for Polymer Research, Mainz 55128, Germany
    More by Ulrike Kraft
  • , 
  • Hagen Klauk
    Hagen Klauk
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    More by Hagen Klauk
  • , 
  • Peter Wahl
    Peter Wahl
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
    More by Peter Wahl
    Orcidhttps://orcid.org/0000-0002-8635-1519
  • , 
  • Andrés Arnau
    Andrés Arnau
    Donostia International Physics Center, E-20018 Donostia - San Sebastián, Spain
    Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología UPV/EHU and Material Physics Center (MPC), Centro Mixto CSIC-UPV/EHU, E-20018 Donostia - San Sebastián, Spain
    More by Andrés Arnau
    Orcidhttps://orcid.org/0000-0001-5281-3212
  • , and 
  • Uta Schlickum*
    Uta Schlickum
    Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    Institute of Applied Physics and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, 38104 Braunschweig, Germany
    *[email protected], [email protected]
    More by Uta Schlickum
Cite this: J. Phys. Chem. Lett. 2023, 14, 8, 2072–2077
Publication Date (Web):February 17, 2023
https://doi.org/10.1021/acs.jpclett.2c03575

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Abstract

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The changes of properties and preferential interactions based on subtle energetic differences are important characteristics of organic molecules, particularly for their functionalities in biological systems. Only slightly energetically favored interactions are important for the molecular adsorption and bonding to surfaces, which define their properties for further technological applications. Here, prochiral tetracenothiophene molecules are adsorbed on the Cu(111) surface. The chiral adsorption configurations are determined by Scanning Tunneling Microscopy studies and confirmed by first-principles calculations. Remarkably, the selection of the adsorption sites by chemically different moieties of the molecules is dictated by the arrangement of the atoms in the first and second surface layers. Furthermore, we have investigated the thermal effects on the direct desulfurization reaction that occurs under the catalytic activity of the Cu substrate. This reaction leads to a product that is covalently bound to the surface in chiral configurations.

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How molecules adsorb on crystalline surfaces is a key element in designing and producing different molecular systems, as well as in controlling their functionalities. The main factors that define the molecular adsorption characteristics are the molecule–surface interaction and the energetics of dynamic processes on surfaces (such as diffusion, conformational changes, rotations, etc.) and the intermolecular interactions. (1) These factors play a fundamental role in self-assembly and the bottom-up growth techniques for producing macromolecular systems (2−5) and molecular structures with various geometries (2,6−14) and chirality. (4,7,8,12,15−20) These arrangements are of high interest for applications in molecular electronics, (6,9,10,18,19,21−25) optoelectronics, (26−28) adsorption-induced molecular magnetism, (29−31) as well as molecular surface chemistry and catalysis. (2,5,26)
Furthermore, the adsorption properties associated with induced catalytic activity at metallic surfaces can be responsible for the formation of new molecular structures and materials. (32−34) A particular example is the desulfurization reaction, required for the removal of sulfur atoms from crude oils, due to the harmful effects of sulfur compounds in the natural environment. (35−37) In previous studies, we have investigated the electric-field-induced desulfurization reaction of tetracenothiophene (TCT) molecules adsorbed on a Cu(111) surface (38) and its effect on the molecular conductance across the molecular derivative product TC-D. (39) Here, we analyze the adsorption characteristics and the effect of the interaction of TCT and TC-D molecules with the surface and subsurface substrate atoms on the surface-induced chirality. In addition, quantitative details on the thermally induced desulfurization reaction of the thiophene group of the TCT are provided.
Tetracenothiophene Adsorption on Cu(111). Intact TCT molecules (see molecular structure in Figure 1a) are deposited in a submonolayer regime onto the Cu(111) surface, maintaining the substrate temperature below 280 K. The molecules are adsorbed with their long axis along the high-symmetry crystallographic directions of the substrate (Figure 1a). In the topographic STM images, the molecules have an asymmetric “dumbbell-like” appearance, with the brighter side at the thiophene unit. (38,39) The images were acquired at a temperature of about 6 K (Figure 1b).

Figure 1

Figure 1. Tetracenothiophene (TCT) adsorption on Cu(111). (a) Molecular structure of TCT. (b) STM topography showing several TCT molecules adsorbed along the high-symmetry crystallographic directions of the Cu(111) surface. (c) Apparent height profile of a TCT molecule, with the highest side corresponding to the thiophene moiety.

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The alignment of adsorbed TCT molecules with respect to the surface and the subsurface Cu atoms relies on the interplay between the positions of the two chemically different parts of the molecule, i.e., the S-containing thiophene group and the acene group. This phenomenon is often encountered during the adsorption of organic molecules that have different functional groups. (8−11,17,18,29,40) The aromatic rings of organic molecules adsorb mostly centered on the hollow sites of a (111) crystal surface. (1,6,7,9,11,15,21,22,38,41,42) Moreover, the fine details of the adsorption geometry may also depend on the subsurface structure, (1,7,9,11,15,22,24,40−42) if fcc-hollow and hcp-hollow sites are not equivalent sites for preferable adsorption. Indeed, benzene units preferentially adsorb at hcp-hollow sites, (1,22,41,42) and thiophene rings on Cu(111) have a tendency to adsorb with the S atoms on top of a Cu surface atom. (21,25,38,43,44) Additionally, the geometry and strength of the interactions between the other functional groups and the surface or the intermolecular interactions between them might also induce misalignments and adsorption on the fcc-hollow site. (7,11,21,40)
To obtain a quantitative understanding of the adsorption configuration of TCT molecules and the registry with Cu surface atoms on Cu(111), we have performed a theoretical study of the different adsorption sites using density functional theory calculations that include van der Waals interactions. In Figure 2a, ball-and-stick models of the optimized adsorption conformations of TCT/Cu(111) are shown. The most stable configuration follows the preferential adsorption tendencies, in which the S atom is placed on a Cu-atop position, while the acene group has the benzene units centered on the hcp-hollow sites. The difference in the relative adsorption energy compared to the adsorption on the hollow-fcc is 97.9 meV (Figure 2b). In consequence, molecules preferentially adsorb along the high-symmetry crystallographic [−1 1 0] axis of the surface.

Figure 2

Figure 2. Preferential adsorption of TCT on Cu(111) and induced chirality. (a) Optimized adsorption geometry of TCT adsorption on the Cu(111) surface, revealing the favorable adsorption of the thiophene unit with the sulfur atom on top of a Cu atom and the acene rings on a hollow position, both the hollow-hcp and the hollow-fcc sites. (b) Relative adsorption energy difference between the two adsorption configurations, having the most stable arrangement on the hollow-hcp site. (c) Structural model of the TCT adsorption along one crystallographic direction of the Cu(111) surface resulting in a racemic mixture of R-TCT (clockwise) and S-TCT (anticlockwise) enantiomers with respect to the mirror planes perpendicular to the surface. (d) Schematic representation with half arrows of the R-TCT and S-TCT molecules. (e) Chiral geometry of TCT molecules adsorbed along the 3-fold symmetry axes of the surface with an R′ (clockwise) favorable and an S′ (anticlockwise) unfavorable configuration.

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The prochiral TCT molecules, due to a surface-induced chirality, arise as “clockwise” R-TCT and “anticlockwise” S-TCT enantiomers (Figure 2c, d). Examining the molecules along one specific symmetry axis shows that the molecules on the hcp-hollow and fcc-hollow sites are mirror images with respect to this symmetry axis, since only then the requirement of the site-specific adsorption is fulfilled, with the S atom atop and acene rings on hollow positions (Figure 2c, d). In addition, considering the 3-fold symmetry of the surface and the selection rule of the two hollow positions for the molecular adsorption, the favorable hcp-hollow and unfavorable fcc-hollow sites can be assigned. This results in chiral geometries labeled R′ (clockwise) and S′ (anticlockwise) (Figure 2e). Besides the induced chirality, the adsorption sites are involved in the surface-activated TCT desulfurization, as presented in the following.
Direct Desulfurization Reaction of Tetracenothiophene. As previously mentioned, (39) the adsorption of TCT on the Cu(111) surface at room temperature activates the cleavage of the S–C bonds from a portion of the adsorbed molecules and results in a desulfurized tetraceno derivative TC-D being strongly bound to the surface. In Figure 3a, the electronic states of the TCT and TC-D molecules close to the Fermi energy are mapped-out with a functionalized tip. For these measurements, a TCT molecule was attached from the surface to the tip apex, following a vertical manipulation procedure. As we have already shown, (38) the desulfurization reaction leads to a reduction in the local density of states at the location of the pristine thiophene unit and the appearance of a darker feature at the former position of the S atom. The latter corresponds to the modification of the lowest unoccupied molecular orbital (LUMO) of the TCT and TC-D species, as the simulated STM image suggests (38) (Figure 3b, c). Additionally, the sulfur atom is found to be repelled away from the molecule. An example of an aggregation that most likely corresponds to desulfurized S atoms is encircled in Figure 3a. In order to allow a strong bonding of the desulfurized derivative moiety, the reaction induces a slight misalignment of the TC-D acene rings with respect to the surface atoms (Figure 3b, c).

Figure 3

Figure 3. Thermally induced desulfurization reaction of TCT under the catalytic activity of Cu(111). (a) STM images acquired with a functionalized tip of the TCT and TC-D molecules following adsorption at a temperature of about 300 K. Half arrows mark each molecular isomer. (b, c) Zoom-in images (marked with rectangles in panel (a) together with the STM simulations in the Tersoff–Hamann approximation of the molecular aspect (38) and of the calculated molecular structure of the TCT and TC-D molecules. (d) Arrhenius plot of the TCT desulfurization reaction.

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Concerning the effects of temperature on the catalytically assisted desulfurization reaction of the thiophene group of the TCT molecules, the analysis of the reaction rate (P) as a function of the Cu substrate temperature (T) during the deposition shows a dependence that follows the Arrhenius law (Figure 3d). This is described by the equation: P=Ae−Ea/kBT, where Ea is the activation energy, kB is the Boltzmann constant, and A is the pre-exponential factor. The activation energy determined experimentally from the Arrhenius plot is 0.50 ± 0.02 eV, a value close to the one obtained theoretically of about 0.66 eV. (38) The extracted value of A is (6.22 ± 7.65) × 10 (5) s–1. The reaction is exothermic. (38) The released energy contributes to the expulsion of the S atom from the molecule (38) and may influence the reaction of the molecules in the close surrounding. If the coverage of TCT was increased, an increase of the reaction probability from 30–40% to 55–65% was observed (for details, see Supporting Information). In this case the molecular coverage was increased from approximately 10% to 50% on the Cu(111) surface kept at a temperature of about 300 K during adsorption.
A careful analysis of the orientation of the TC-D molecules at high coverage reveals that some molecules are located on the less convenient surface adsorption sites due to certain geometrical constraints. The high-resolution STM images in Figure 4 were acquired with a functionalized tip. Classifying the TC-D enantiomers leads to a majority of molecules (approximately 96%) arranged in the favorable configuration with the ethylene end group positioned on one side of the symmetry axes of the surface (R′ conformations of the R-TC-D and S-TC-D enantiomers). This is based on the selection rule associated with the preferential adsorption position at the hollow sites, as also confirmed by density functional theory calculations. However, if two molecules are extremely close to each other, one of the molecules adopts the less favorable arrangement with respect to the subsurface atoms, i.e., the S′ conformation (Figure 4a, b, red marks). From the structural analysis of the data we assume that this arrangement is mediated by both molecule–surface and intermolecular interactions. The difference in the adsorption energy between the favorable hcp registry and the fcp registry of the acene rings of the molecules on the Cu(111) is relatively low. Thus, already weak intermolecular interactions can dominate over molecule-surface interaction and lead to the rearrangement of the adsorption geometry to the less favorable position.

Figure 4

Figure 4. STM images of the racemic mixture of TCT and TC-D molecules. (a) Topographic overview image acquired with a functionalized tip. Yellow half arrows are used to mark the TC-D enantiomers. (b) Zoom-in images of TC-D dimers showing different occurrences, with an unfavorable S′ configuration (red marks) of a TC-D molecule in the left panel.

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In summary, we have investigated the adsorption characteristics of TCT molecules and of molecules of the desulfurized derivative TC-D on Cu(111). Our studies demonstrate the preferential adsorption conformation being along the high-symmetry axes of the surface with the thiophene unit atop a Cu atom and the acene rings on the hcp-hollow sites. This is confirmed by density functional theory calculations. The preferred adsorption geometry induces a molecular chirality of right-handed and left-handed enantiomers of a prochiral building block and of the TC-D product. Additionally, as the molecular coverage is increased, certain constraints and competing interactions give rise to the formation of different aggregates with both types of enantiomers. Under these conditions, dimers and, occasionally, trimers with different orientations are formed as well. These findings open the possibility to grow superstructures with specific functionalities and chiral properties tunable by the marginal energetic changes in the adsorption conformation.

Experimental and Computational Methods

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Experimental Procedures. Tetraceno[2,3-b]thiophene (TCT) molecules were synthesized by following the processes described in detail in refs (39and45). The Cu(111) substrate was cleaned before each deposition by standard procedures of Ar+ ion etching and subsequent annealing to a temperature of 800 K. TCT was deposited under ultrahigh vacuum conditions by thermal sublimation onto the Cu(111) surface held at a constant temperature between 275 and 325 K during the deposition. In order to study the thermal effects on the desulfurization reaction, the deposition of an approximately identical amount of molecules corresponding to a surface coverage of about 10% was realized with the same rate and deposition time (10 min) onto the substrate held at the defined temperature. After each deposition, the sample was immediately transferred in situ, in a time span of a few minutes, into the STM operating at a cryogenic temperature of about 6 K. The STM measurements were carried out in constant-current mode by applying the bias voltages to the sample. For the determination of the reaction probability as a function of the substrate temperature during the deposition, a minimum of two separate depositions were carried out for each defined substrate temperature. Several STM images were acquired for each sample on different macroscopic regions containing more than 600 molecules. STM images with submolecular resolution were obtained with a functionalized tip having a TCT molecule attached by vertical manipulation to the tip apex. This process consists of first imaging the TCT molecule to be picked up. Then, the STM tip is placed on top of the molecule, the feedback loop is switched off, and the tip is approached toward the molecule. At a distance where attractive forces are dominant, the molecule attaches to and remains at the tip apex when the tip is lifted from the surface again.
The WSxM software (46) was employed for the analysis of the STM images.
Computational Methods. Calculations were performed in the frame of density functional theory (DFT), under the generalized gradient approximation (GGA) with the vdW-DF-cx functional. (47) This allows us to include van der Waals forces, with the Vienna ab initio simulation package (VASP). (48)
The electron density was expanded in a plane-wave basis with a cutoff energy of 500 eV, and the interaction between electrons and nuclei was described with the projector augmented wave (PAW) pseudopotentials from the VASP database. Reciprocal space was sampled using a 3 × 3 × 1 k-mesh, following the Monkhorst–Pack scheme.
To simulate the adsorption of the molecules on the Cu(111) surface, we used a supercell that consists of a 4-layer slab of 8 × 8 Cu atoms. A vacuum gap with a separation of ∼15 Å was used to avoid spurious interaction between the molecule and the closest replica.
We used a convergence criterion of 10–5 eV for the electron density during optimizations. We consider a structure as converged when all the Hellman–Feyman forces are smaller than 0.01 eV/Å, for the degrees of freedom that we allow to relax (xyz coordinates of all the atoms in the molecule and z of the outermost metal layer).
The VESTA software (49) was employed for the ball-and-stick representations.

Supporting Information

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The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.jpclett.2c03575.

  • Experimental results on the desulfurization reaction of TCT molecules by adsorption at a temperature of about 300 K on Cu(111) (PDF)

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Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

Author Information

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  • Corresponding Authors
    • Bogdana Borca - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany;  National Institute of Materials Physics, Atomistilor 405A, 077125 Magurele, Ilfov, Romania;  Orcidhttps://orcid.org/0000-0001-5485-4536;  Email: [email protected]
    • Uta Schlickum - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany;  Institute of Applied Physics and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, 38104 Braunschweig, Germany;  Email: [email protected]
  • Authors
    • Tomasz Michnowicz - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    • Fernando Aguilar-Galindo - Donostia International Physics Center, E-20018 Donostia - San Sebastián, Spain;  Orcidhttps://orcid.org/0000-0003-2751-5592
    • Rémi Pétuya - Donostia International Physics Center, E-20018 Donostia - San Sebastián, Spain;  Present Address: (R.P.) Nextmol (Bytelab Solutions SL), Barcelona 08018, Spain;  Orcidhttps://orcid.org/0000-0002-3118-6966
    • Marcel Pristl - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    • Verena Schendel - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    • Ivan Pentegov - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    • Ulrike Kraft - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany;  Max Planck Institute for Polymer Research, Mainz 55128, Germany
    • Hagen Klauk - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
    • Peter Wahl - Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany;  SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom;  Orcidhttps://orcid.org/0000-0002-8635-1519
    • Andrés Arnau - Donostia International Physics Center, E-20018 Donostia - San Sebastián, Spain;  Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología UPV/EHU and Material Physics Center (MPC), Centro Mixto CSIC-UPV/EHU, E-20018 Donostia - San Sebastián, Spain;  Orcidhttps://orcid.org/0000-0001-5281-3212
  • Funding

    Open access funded by Max Planck Society.

  • Notes
    The authors declare no competing financial interest.

Acknowledgments

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The authors acknowledge the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy-EXC-2123 Quantum Frontiers - 390837967; Core program PC2-PN23080202 and the PN-III-P2-2.1-PED-2021-0378 (contract no. 575PED/2022) granted projects, financed by the Romanian Ministry of Research, Innovation and Digitalization/UEFISCDI; and the generous allocation of computer time at the computing center of Donostia International Physics Center and at the Red Española de Supercomputación (project QHS-2021-2-0019). A.A. acknowledges support from Project No. PID2019-103910GB-I00, funded by MCIN/AEI/10.13039/501100011033/ and FEDER Una manera de hacer Europa, and Project No. IT-1527-22 funded by the Basque Government.

References

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This article references 49 other publications.

  1. 1
    Sacchi, M.; Singh, P.; Chisnall, D. M.; Ward, D. J.; Jardine, A. P.; Allison, W.; Ellis, J.; Hedgeland, H. The Dynamics of Benzene on Cu(111): A Combined Helium Spin Echo and Dispersion-Corrected DFT Study into the Diffusion of Physisorbed Aromatics on Metal Surfaces. Faraday Discuss. 2017, 204, 471– 485,  DOI: 10.1039/C7FD00095B
    [Crossref], [PubMed], [CAS], Google Scholar
    1
    The dynamics of benzene on Cu(111): a combined helium spin echo and dispersion-corrected DFT study into the diffusion of physisorbed aromatics on metal surfaces
    Sacchi, M.; Singh, P.; Chisnall, D. M.; Ward, D. J.; Jardine, A. P.; Allison, W.; Ellis, J.; Hedgeland, H.
    Faraday Discussions (2017), 204 (Complex Molecular Surfaces and Interfaces), 471-485CODEN: FDISE6; ISSN:1359-6640. (Royal Society of Chemistry)
    We use helium spin-echo spectroscopy (HeSE) to investigate the dynamics of the diffusion of benzene adsorbed on Cu(111). The results of these measurements show that benzene moves on the surface through an activated jump-diffusion process between the adsorption sites on a Bravais lattice. D. Functional Theory (DFT) calcns. with van der Waals (vdW) corrections help us understand that the mol. diffuses by jumping through non-degenerate hollow sites. The results of the calcns. shed light on the nature of the binding interaction between this prototypical arom. mol. and the metallic surface. The highly accurate HeSE exptl. data provide a quant. stringent benchmark for the vdW correction schemes applied to the DFT calcns. and we compare the performances of several dispersion interaction schemes.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXmslShs7w%253D&md5=93e834d43c9dcbc3f2326ee43d965ac1
  2. 2
    Cirera, B.; Riss, A.; Mutombo, P.; Urgel, J. I.; Santos, J.; Di Giovannantonio, M.; Widmer, R.; Stolz, S.; Sun, Q.; Bommert, M.; Fasel, R.; Jelínek, P.; Auwärter, W.; Martín, N.; Écija, D. On-Surface Synthesis of Organocopper Metallacycles through Activation of Inner Diacetylene Moieties. Chem. Sci. 2021, 12, 12806– 12811,  DOI: 10.1039/D1SC03703J
    [Crossref], [PubMed], [CAS], Google Scholar
    2
    On-surface synthesis of organocopper metallacycles through activation of inner diacetylene moieties
    Cirera Borja; Urgel Jose I; Santos Jose; Martin Nazario; Ecija David; Riss Alexander; Auwarter Willi; Mutombo Pingo; Jelinek Pavel; Urgel Jose I; Di Giovannantonio Marco; Widmer Roland; Stolz Samuel; Sun Qiang; Bommert Max; Fasel Roman; Santos Jose; Martin Nazario; Di Giovannantonio Marco; Stolz Samuel; Fasel Roman
    Chemical science (2021), 12 (38), 12806-12811 ISSN:2041-6520.
    The design of organometallic complexes is at the heart of modern organic chemistry and catalysis. Recently, on-surface synthesis has emerged as a disruptive paradigm to design previously precluded compounds and nanomaterials. Despite these advances, the field of organometallic chemistry on surfaces is still at its infancy. Here, we introduce a protocol to activate the inner diacetylene moieties of a molecular precursor by copper surface adatoms affording the formation of unprecedented organocopper metallacycles on Cu(111). The chemical structure of the resulting complexes is characterized by scanning probe microscopy and X-ray photoelectron spectroscopy, being complemented by density functional theory calculations and scanning probe microscopy simulations. Our results pave avenues to the engineering of organometallic compounds and steer the development of polyyne chemistry on surfaces.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BB2cjls1CjsA%253D%253D&md5=fbff835b3fc2847c0205790755810d5f
  3. 3
    Heim, D.; Seufert, K.; Auwärter, W.; Aurisicchio, C.; Fabbro, C.; Bonifazi, D.; Barth, J. V. Surface-Assisted Assembly of Discrete Porphyrin-Based Cyclic Supramolecules. Nano Lett. 2010, 10, 122– 128,  DOI: 10.1021/nl9029994
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    3
    Surface-Assisted Assembly of Discrete Porphyrin-Based Cyclic Supramolecules
    Heim, Daniel; Seufert, Knud; Auwaerter, Willi; Aurisicchio, Claudia; Fabbro, Chiara; Bonifazi, Davide; Barth, Johannes V.
    Nano Letters (2010), 10 (1), 122-128CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
    The authors employed de novo synthesized porphyrin modules to construct discrete cyclic supramol. architectures supported on a copper surface. The programmed geometry and functionality of the mol. modules together with their conformational flexibility and substrate interaction yields sym. discrete assemblies, including dimers and chains as well as three- to six-membered cyclic structures. The area of the mol. cavities is extended by creating bicomponent structures combining building blocks with different symmetry.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXhtlKmsrjN&md5=ce4251ce822c2c8ea764b0abfdea2758
  4. 4
    Kaposi, T.; Joshi, S.; Hoh, T.; Wiengarten, A.; Seufert, K.; Paszkiewicz, M.; Klappenberger, F.; Ecija, D.; D̵ord̵ević, L.; Marangoni, T.; Bonifazi, D.; Barth, J. V.; Auwärter, W. Supramolecular Spangling, Crocheting, and Knitting of Functionalized Pyrene Molecules on a Silver Surface. ACS Nano 2016, 10, 7665– 7674,  DOI: 10.1021/acsnano.6b02989
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    4
    Supramolecular Spangling, Crocheting, and Knitting of Functionalized Pyrene Molecules on a Silver Surface
    Kaposi, Tobias; Joshi, Sushobhan; Hoh, Tobias; Wiengarten, Alissa; Seufert, Knud; Paszkiewicz, Matheusz; Klappenberger, Florian; Ecija, David; Djordjevic, Luka; Marangoni, Tomas; Bonifazi, Davide; Barth, Johannes V.; Auwaerter, Willi
    ACS Nano (2016), 10 (8), 7665-7674CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    Pyrenes, as photoactive polycyclic arom. hydrocarbons (PAHs), represent promising modules for the bottom-up assembly of functional nanostructures. Here, we introduce the synthesis of a family of pyrene derivs. peripherally functionalized with pyridin-4-ylethynyl termini and comprehensively characterize their self-assembly abilities on a smooth Ag(111) support by scanning tunneling microscopy. By deliberate selection of no. and geometric positioning of the pyridyl-terminated substituents, two-dimensional arrays, one-dimensional coordination chains, and chiral, porous kagom´e-type networks can be tailored. A comparison to phenyl-functionalized ref. pyrenes, not supporting the self-assembly of ordered structures at low coverage, highlights the role of the pyridyl moieties for supramol. crocheting and knitting. Furthermore, we demonstrate the selective spangling of pores in the two-dimensional pyrene assemblies by a distinct no. of iodine atoms as guests by atomically resolved imaging and complementary XPS.
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  5. 5
    Lawrence, J.; Mohammed, M. S. G.; Rey, D.; Aguilar-Galindo, F.; Berdonces-Layunta, A.; Peña, D.; de Oteyza, D. G. Reassessing Alkyne Coupling Reactions While Studying the Electronic Properties of Diverse Pyrene Linkages at Surfaces. ACS Nano 2021, 15, 4937– 4946,  DOI: 10.1021/acsnano.0c09756
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    5
    Reassessing Alkyne Coupling Reactions While Studying the Electronic Properties of Diverse Pyrene Linkages at Surfaces
    Lawrence, James; Mohammed, Mohammed S. G.; Rey, Dulce; Aguilar-Galindo, Fernando; Berdonces-Layunta, Alejandro; Pena, Diego; de Oteyza, Dimas G.
    ACS Nano (2021), 15 (3), 4937-4946CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    The combination of alkyne and halogen functional groups in the same mol. allows for the possibility of many different reactions when utilized in on-surface synthesis. Here, we use a pyrene-based precursor with both functionalities to examine the preferential reaction pathway when it is heated on an Au(111) surface. Using high-resoln. bond-resolving scanning tunneling microscopy, we identify multiple stable intermediates along the prevailing reaction pathway that initiate with a clearly dominant Glaser coupling, together with a multitude of other side products. Importantly, control expts. with reactants lacking the halogen functionalization reveal the Glaser coupling to be absent and instead show the prevalence of non-dehydrogenative head-to-head alkyne coupling. We perform scanning tunneling spectroscopy on a rich variety of the product structures obtained in these expts., providing key insights into the strong dependence of their HOMO-LUMO gaps on the nature of the intramol. coupling. A clear trend is found of a decreasing gap that is correlated with the conversion of triple bonds to double bonds via hydrogenation and to higher levels of cyclization, particularly with nonbenzenoid product structures. We rationalize each of the studied cases.
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  6. 6
    Smerdon, J. A.; Bode, M.; Guisinger, N. P.; Guest, J. R. Monolayer and Bilayer Pentacene on Cu(111). Phys. Rev. B 2011, 84, 165436,  DOI: 10.1103/PhysRevB.84.165436
    [Crossref], [CAS], Google Scholar
    6
    Monolayer and bilayer pentacene on Cu(111)
    Smerdon, J. A.; Bode, M.; Guisinger, N. P.; Guest, J. R.
    Physical Review B: Condensed Matter and Materials Physics (2011), 84 (16), 165436/1-165436/7CODEN: PRBMDO; ISSN:1098-0121. (American Physical Society)
    The morphol. and electronic structure of pentacene (Pn) deposited on Cu(111) was studied using scanning tunneling microscopy (STM) and spectroscopy (STS). Deposition of a multilayer followed by annealing to reduce coverage to a monolayer results in the formation of either of two unique phases: a two-dimensional herringbone structure previously unobserved for any linear acene to our knowledge, or a "random-tiling" structure. Coverage greater than a monolayer promotes the formation of a bilayer phase similar to that obsd. for Pn/Ag(111). STS shows that the electronic structure of the first layer is strongly modified due to its proximity to the substrate, while the second layer exhibits nearly bulklike electronic structure.
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  7. 7
    Mairena, A.; Zoppi, L.; Seibel, J.; Tröster, A. F.; Grenader, K.; Parschau, M.; Terfort, A.; Ernst, K. H. Heterochiral to Homochiral Transition in Pentahelicene 2D Crystallization Induced by Second-Layer Nucleation. ACS Nano 2017, 11, 865– 871,  DOI: 10.1021/acsnano.6b07424
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    7
    Heterochiral to Homochiral Transition in Pentahelicene 2D Crystallization Induced by Second-Layer Nucleation
    Mairena, Anais; Zoppi, Laura; Seibel, Johannes; Troster, Alix F.; Grenader, Konstantin; Parschau, Manfred; Terfort, Andreas; Ernst, Karl-Heinz
    ACS Nano (2017), 11 (1), 865-871CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    Gaining insight into mol. recognition at the mol. level, in particular, during nucleation of crystallites, is challenging and calls for studying well-defined model systems. Investigated by means of submol. resoln. scanning tunneling microscopy and theor. mol. modeling, we report chiral recognition phenomena in the 2D crystn. of the helical chiral arom. hydrocarbon pentahelicene on a Cu(111) surface. Homochiral, van der Waals bonded dimers constitute building blocks for self-assembly but form heterochiral as well as homochiral long-range-ordered structures. 2D racemate crystals, built up by homochiral dimers of both enantiomers, are obsd. at coverages close to a full monolayer. As soon as the coverage leads to second-layer nucleation, the dense racemate phase in the first layer disappears and a homochiral dimer conglomerate phase of lower 2D d. appears. Our results show that, at the onset of second-layer nucleation, a local change of enantiomeric compn. in the first layer occurs, causing the transition from a 2D racemate to a 2D conglomerate.
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  8. 8
    Schlickum, U.; Decker, R.; Klappenberger, F.; Zoppellaro, G.; Klyatskaya, S.; Auwarter, W.; Neppl, S.; Kern, K.; Brune, H.; Ruben, M.; Barth, J. V. Chiral Kagomé Lattice from Simple Ditopic Molecular Bricks. J. Am. Chem. Soc. 2008, 130, 11778– 11782,  DOI: 10.1021/ja8028119
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    8
    Chiral Kagome Lattice from Simple Ditopic Molecular Bricks
    Schlickum, U.; Decker, R.; Klappenberger, F.; Zoppellaro, G.; Klyatskaya, S.; Auwarter, W.; Neppl, S.; Kern, K.; Brune, H.; Ruben, M.; Barth, J. V.
    Journal of the American Chemical Society (2008), 130 (35), 11778-11782CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    Self-assembly techniques allow for the fabrication of highly organized architectures with at.-level precision. Here, we report on mol.-level scanning tunneling microscopy observations demonstrating the supramol. engineering of complex, regular, and long-range ordered periodic networks on a surface at. lattice using simple linear mol. bricks. The length variation of the employed de novo synthesized linear dicarbonitrile polyphenyl mols. translates to distinct changes of the bonding motifs that lead to hierarchic order phenomena and unexpected changes of the surface tessellations. The achieved 2D org. networks range from a close-packed chevron pattern via a rhombic network to a hitherto unobserved supramol. chiral kagome lattice.
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  9. 9
    Pivetta, M.; Pacchioni, G. E.; Schlickum, U.; Barth, J. V.; Brune, H. Formation of Fe Cluster Superlattice in a Metal-Organic Quantum-Box Network. Phys. Rev. Lett. 2013, 110, 086102,  DOI: 10.1103/PhysRevLett.110.086102
    [Crossref], [PubMed], [CAS], Google Scholar
    9
    Formation of Fe cluster superlattice in a metal-organic quantum-box network
    Pivetta, Marina; Pacchioni, Giulia E.; Schlickum, Uta; Barth, Johannes V.; Brune, Harald
    Physical Review Letters (2013), 110 (8), 086102/1-086102/5CODEN: PRLTAO; ISSN:0031-9007. (American Physical Society)
    The authors report on the self-assembly of Fe adatoms on a Cu(111) surface that is patterned by a metal-org. honeycomb network, formed by coordination of dicarbonitrile pentaphenyl mols. with Cu adatoms. Fe atoms landing on the metal surface are mobile and steered by the quantum confinement of the surface state electrons towards the center of the network hexagonal cavities. In cavities hosting more than one Fe, preferential interat. distances are obsd. The adatoms in each hexagon aggregate into a single cluster upon gentle annealing. These clusters are again centered in the cavities and their size is discerned by their distinct apparent heights.
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  10. 10
    Stradi, D.; Borca, B.; Barja, S.; Garnica, M.; Diaz, C.; Rodriguez-Garcia, J. M.; Alcami, M.; Vázquez de Parga, A. L.; Miranda, R.; Martin, F. Understanding the Self-Assembly of TCNQ on Cu(111): A Combined Study Based on Scanning Tunnelling Microscopy Experiments and Density Functional Theory Simulations. RSC Adv. 2016, 6, 15071– 15079,  DOI: 10.1039/C5RA26320D
    [Crossref], [CAS], Google Scholar
    10
    Understanding the self-assembly of TCNQ on Cu(111): a combined study based on scanning tunnelling microscopy experiments and density functional theory simulations
    Stradi, Daniele; Borca, Bogdana; Barja, Sara; Garnica, Manuela; Diaz, Cristina; Rodriguez-Garcia, Josefa M.; Alcami, Manuel; Vazquez de Parga, Amadeo L.; Miranda, Rodolfo; Martin, Fernando
    RSC Advances (2016), 6 (18), 15071-15079CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
    The structure of self-assembled monolayers of 7,7',8,8'-tetracyano-p-quinodimethane (TCNQ) adsorbed on Cu(111) has been studied using a combination of scanning tunnelling microscopy (STM) expts. and d. functional theory (DFT) calcns. We show that the polymorphism of the self-assembled mol. layer can be controlled by tuning of the exptl. conditions under which the deposition is carried out. When the Cu(111) substrate is held above room temp. (TCu(111) = 350 K) during deposition, a structure is formed in which the two mols. in the unit cell are oriented one perpendicular to the other. Conversely, when the substrate is held at room temp. during deposition and slightly annealed afterwards, a more complex structure with five mols. per unit cell is formed. DFT calcns. complement the exptl. results by revealing that the building blocks of the two superstructures are two mutually orthogonal adsorption configurations of the mol. The relative stability between the two obsd. polymorphs is reproduced by models of the two superstructures based on these two adsorption configurations.
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  11. 11
    Zhong, Q.; Ebeling, D.; Tschakert, J.; Gao, Y.; Bao, D.; Du, S.; Li, C.; Chi, L.; Schirmeisen, A. Symmetry Breakdown of 4,4”-Diamino-p-Terphenyl on a Cu(111) Surface by Lattice Mismatch. Nat. Commun. 2018, 9, 3277,  DOI: 10.1038/s41467-018-05719-y
    [Crossref], [PubMed], [CAS], Google Scholar
    11
    Symmetry breakdown of 4,4"-diamino-p-terphenyl on a Cu(111) surface by lattice mismatch
    Zhong Qigang; Chi Lifeng; Ebeling Daniel; Tschakert Jalmar; Schirmeisen Andre; Gao Yixuan; Bao Deliang; Du Shixuan; Li Chen
    Nature communications (2018), 9 (1), 3277 ISSN:.
    Site-selective functionalization of only one of two identical chemical groups within one molecule is highly challenging, which hinders the production of complex organic macromolecules. Here we demonstrate that adsorption of 4,4"-diamino-p-terphenyl on a metal surface leads to a dissymmetric binding affinity. With low temperature atomic force microscopy, using CO-tip functionalization, we reveal the asymmetric adsorption geometries of 4,4"-diamino-p-terphenyl on Cu(111), while on Au(111) the symmetry is retained. This symmetry breaking on Cu(111) is caused by a lattice mismatch and interactions with the subsurface atomic layer. The dissymmetry results in a change of the binding affinity of one of the amine groups, leading to a non-stationary behavior under the influence of the scanning tip. Finally, we exploit this dissymmetric binding affinity for on-surface self-assembly with 4,4"-diamino-p-terphenyl for side-preferential attachment of 2-triphenylenecarbaldehyde. Our findings provide a new route towards surface-induced dissymmetric activation of a symmetric compound.
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  12. 12
    Morf, P.; Ballav, N.; Putero, M.; von Wrochem, F.; Wessels, J. M.; Jung, T. A. (2010). Supramolecular Structures and Chirality in Dithiocarbamate Self-Assembled Monolayers on Au (111). J. Phys. Chem. Lett. 2010, 1, 813– 816,  DOI: 10.1021/jz900435w
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    12
    Supramolecular Structures and Chirality in Dithiocarbamate Self-Assembled Monolayers on Au(111)
    Morf, Peter; Ballav, Nirmalya; Putero, Magali; von Wrochem, Florian; Wessels, Jurina M.; Jung, Thomas A.
    Journal of Physical Chemistry Letters (2010), 1 (5), 813-816CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
    We report the observation of supramol. structures in a self-assembled monolayer (SAM) of diethyldithiocarbamate (DEDTC) on the Au(111) substrate. While all sulfur atoms are found to be covalently anchored to the gold substrate for both DEDTC and DT (decanethiol) monolayers, the self-assembly behavior of DEDTC has been obsd. to be distinctively different from that of DT. We have found hexagonally arranged trimeric domains of DEDTC mols. in two 30° rotated domains, which we assign to a pattern of chiral trimeric domains. The trimers belong to the C3 point group, and the supramol. assembly shows a (2√3 × 2√3)R15° surface structure.
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  13. 13
    Li, D.; Ding, Y.; Wang, X.; Xu, W. On-Surface Fabrication of Bimetallic Metal–Organic Frameworks through the Synergy and Competition among Noncovalent Interactions. J. Phys. Chem. Lett. 2021, 12, 5228– 5232,  DOI: 10.1021/acs.jpclett.1c00942
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    13
    On-surface fabrication of bimetallic metal-organic frameworks through synergy and competition among noncovalent interactions
    Li, Donglin; Ding, Yuanqi; Wang, Xinyi; Xu, Wei
    Journal of Physical Chemistry Letters (2021), 12 (22), 5228-5232CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
    Two-dimensional metal-org. frameworks (2D-MOFs) are attracting more attention due to their unique properties. Various 2D-MOF structures have been fabricated on surfaces in which either only one kind of metal was incorporated or only one kind of noncovalent interaction was involved in a bimetallic network. However, 2D-MOFs involving different kinds of noncovalent interactions and multiple metal components are more complex and less predictable. Here, we choose the uracil (U) mol. together with alkali metals [sodium (Na) and cesium (Cs)] and a transition metal [iron (Fe)] as model systems and successfully construct two kinds of bimetallic 2D-MOFs through the synergy and competition among noncovalent interactions, which is revealed by the high-resoln. scanning tunneling microscopy imaging and d. functional theory calcns. Such a systematic study may help to improve our fundamental understanding of the interaction mechanism of noncovalent bonds and, moreover, lead to further investigations of the unprecedented functions of surface-supported 2D-MOF structures.
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  14. 14
    Cirera, B.; Giménez-Agulló, N.; Björk, J.; Martínez-Peña, F.; Martin-Jimenez, A.; Rodriguez-Fernandez, J.; Pizarro, A. M.; Otero, R.; Gallego, J. M.; Ballester, P.; Galan-Mascaros, J. R.; Ecija, D. Thermal Selectivity of Intermolecular Versus Intramolecular Reactions on Surfaces. Nat. Commun. 2016, 7, 11002,  DOI: 10.1038/ncomms11002
    [Crossref], [PubMed], [CAS], Google Scholar
    14
    Thermal selectivity of intermolecular versus intramolecular reactions on surfaces
    Cirera, Borja; Gimenez-Agullo, Nelson; Bjork, Jonas; Martinez-Pena, Francisco; Martin-Jimenez, Alberto; Rodriguez-Fernandez, Jonathan; Pizarro, Ana M.; Otero, Roberto; Gallego, Jose M.; Ballester, Pablo; Galan-Mascaros, Jose R.; Ecija, David
    Nature Communications (2016), 7 (), 11002CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
    On-surface synthesis is a promising strategy for engineering heteroat. covalent nanoarchitectures with prospects in electronics, optoelectronics and photovoltaics. Here we report the thermal tunability of reaction pathways of a mol. precursor in order to select intramol. vs. intermol. reactions, yielding monomeric or polymeric phthalocyanine derivs., resp. Deposition of tetra-aza-porphyrin species bearing Et termini on Au(111) held at room temp. results in a close-packed assembly. Upon annealing from room temp. to 275 °C, the mol. precursors undergo a series of covalent reactions via their Et termini, giving rise to phthalocyanine tapes. However, deposition of the tetra-aza-porphyrin derivs. on Au(111) held at 300 °C results in the formation and self-assembly of monomeric phthalocyanines. A systematic scanning tunnelling microscopy study of reaction intermediates, combined with d. functional calcns., suggests a [2+2] cycloaddn. as responsible for the initial linkage between mol. precursors, whereas the monomeric reaction is rationalized as an electrocyclic ring closure.
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  15. 15
    Zint, S.; Ebeling, D.; Ahles, S.; Wegner, H. A.; Schirmeisen, A. Subsurface-Controlled Angular Rotation: Triphenylene Molecules on Au(111) Substrates. J. Phys. Chem. C 2016, 120, 1615– 1622,  DOI: 10.1021/acs.jpcc.5b10602
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    15
    Subsurface-Controlled Angular Rotation: Triphenylene Molecules on Au(111) Substrates
    Zint, Soeren; Ebeling, Daniel; Ahles, Sebastian; Wegner, Hermann A.; Schirmeisen, Andre
    Journal of Physical Chemistry C (2016), 120 (3), 1615-1622CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
    Self-assembly of triphenylene mols. on a reconstructed Au(111) substrate in the submonolayer regime has been studied by scanning tunneling microscopy. Only two different orientations of the planar adsorbed mols. are obsd. At intermediate coverages self-assembly is mainly detd. by repulsive mol.-mol. interactions, leading to a one-to-one ratio of mol. orientations. At 1.0 monolayer coverage, however, a reorientation into close-packed domains occurs, which significantly shifts the ratio of mol. orientations. It is found that this reorientation is controlled by mol.-subsurface interactions, opening new avenues in assembling mols. on surfaces.
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  16. 16
    Kühnle, A.; Linderoth, T. R.; Besenbacher, F. Self-assembly of Monodispersed, Chiral Nanoclusters of Cysteine on the Au (110)-(1× 2) Surface. J. Am. Chem. Soc. 2003, 125, 14680– 14681,  DOI: 10.1021/ja0377403
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    16
    Self-Assembly of Monodispersed, Chiral Nanoclusters of Cysteine on the Au(110)-(1 × 2) Surface
    Kuehnle, Angelika; Linderoth, Trolle R.; Besenbacher, Flemming
    Journal of the American Chemical Society (2003), 125 (48), 14680-14681CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    The self-assembly of monodispersed supramol. nanoclusters was obsd. by scanning tunneling microscopy (STM). The clusters form from the naturally occurring amino acid cysteine by vapor deposition onto the Au(110)-(1 × 2) surface under ultrahigh vacuum conditions. Enantiomerically pure L- and D-cysteine yields clusters with mirror-image STM signatures. Racemic LD-cysteine segregates into homochiral clusters, evidencing specific intermol. interactions during the self-assembly process.
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  17. 17
    Bombis, C.; Weigelt, S.; Knudsen, M. M.; Nørgaard, M.; Busse, C.; Lægsgaard, E.; Besenbacher, F.; Gothelf, K. V.; Linderoth, T. R. Steering Organizational and Conformational Surface Chirality by Controlling Molecular Chemical Functionality. ACS Nano 2010, 4, 297– 311,  DOI: 10.1021/nn9012803
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    17
    Steering Organizational and Conformational Surface Chirality by Controlling Molecular Chemical Functionality
    Bombis, Christian; Weigelt, Sigrid; Knudsen, Martin M.; Noergaard, Martin; Busse, Carsten; Laegsgaard, Erik; Besenbacher, Flemming; Gothelf, Kurt V.; Linderoth, Trolle R.
    ACS Nano (2010), 4 (1), 297-311CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    Mol. chirality on surfaces was widely explored, both for intrinsically chiral mols. and for prochiral mols. that become chiral upon adsorption due to the reduced symmetry which follows from surface confinement. However, little attention was devoted to chiral effects that originate from conformational degrees of freedom for adsorbed mols. Scanning tunneling microscopy was here used to study the self-assembled structures formed when a class of six linear, org. mols. (oligo-phenylene-ethynylenes) are adsorbed on a Au(111) surface under ultrahigh vacuum conditions. All of the studied compds. are intrinsically achiral, but most display conformational chirality in the sense that the mols. can adsorb on the surface in different conformations giving rise to either one of two chiral surface enantiomers or a mirror-sym. achiral meso form. A total of eleven obsd. adsorption structures are systematically studied with respect to conformational chirality as well as point chirality (arising where mol. adsorption locally breaks the substrate symmetry) and organizational chirality (arising from the tiling pattern of the mol. backbones). A no. of interesting correlations are identified between these different levels of chirality. Most importantly, it is possible through control of the terminal group functionalization to steer the oligo(phenylene-ethynylene) mol. backbones into surface assemblies that either display pronounced organizational chirality or have mirror sym. tiling patterns, and it is also possible to control the conformational surface chirality so the compds. preferentially assume either chiral or achiral surface conformers.
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  18. 18
    Masini, F.; Kalashnyk, N.; Knudsen, M. M.; Cramer, J. R.; Lægsgaard, E.; Besenbacher, F.; Gothelf, K. V.; Linderoth, T. R. Chiral Induction by Seeding Surface Assemblies of Chiral Switches. J. Am. Chem. Soc. 2011, 133, 13910– 13913,  DOI: 10.1021/ja205998c
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    18
    Chiral Induction by Seeding Surface Assemblies of Chiral Switches
    Masini, Federico; Kalashnyk, Nataliya; Knudsen, Martin M.; Cramer, Jacob R.; Laegsgaard, Erik; Besenbacher, Flemming; Gothelf, Kurt V.; Linderoth, Trolle R.
    Journal of the American Chemical Society (2011), 133 (35), 13910-13913CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    It is demonstrated by scanning tunneling microscopy that coadsorption of a mol. chiral switch with a complementary, intrinsically chiral induction seed on the Au(111) surface gives globally homochiral mol. assemblies.
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  19. 19
    Grillo, F.; Mugnaini, V.; Oliveros, M.; Francis, S. M.; Choi, D. J.; Rastei, M. V.; Limot, L.; Cepek, C.; Pedio, M.; Bromley, S. T.; Richardson, N. V.; Bucher, J.-P.; Veciana, J. Chiral Conformation at a Molecular Level of a Propeller-Like Open-Shell Molecule on Au (111). J. Phys. Chem. Lett. 2012, 3, 1559– 1564,  DOI: 10.1021/jz3003926
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    19
    Chiral Conformation at a Molecular Level of a Propeller-Like Open-Shell Molecule on Au(111)
    Grillo, Federico; Mugnaini, Veronica; Oliveros, Malena; Francis, Steve M.; Choi, Deung-Jang; Rastei, Mircea V.; Limot, Laurent; Cepek, Cinzia; Pedio, Maddalena; Bromley, Stefan T.; Richardson, Neville V.; Bucher, Jean-Pierre; Veciana, Jaume
    Journal of Physical Chemistry Letters (2012), 3 (11), 1559-1564CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
    A key stage in engineering mol. functional organizations is represented by controlling the supramol. assembly of single mol. building blocks, tectons, into ordered networks. Here, an open-shell, propeller-like mol. was deposited under UHV conditions on Au(111) and its supramol. organization characterized by scanning tunneling microscopy (STM). Racemic islands were obsd. at room temp., and their chirality was imaged at the mol. level at low temp. Modeling further suggests that the obsd. chirally alternating ordering dominated by intermol. interactions is energetically favored. ESR and UV photoemission spectroscopy evidences suggest that the supramol. networks may preserve the open-shell character of the tecton. These results represent a fundamental step forward toward the engineering of purely org. spintronic devices.
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  20. 20
    Dmitriev, A.; Spillmann, H.; Stepanow, S.; Strunskus, T.; Wöll, C.; Seitsonen, A. P.; Lingenfelder, M.; Lin, N.; Barth, J. V.; Kern, K. Asymmetry Induction by Cooperative Intermolecular Hydrogen Bonds in Surface-Anchored Layers of Achiral Molecules. ChemPhysChem 2006, 7, 2197– 2204,  DOI: 10.1002/cphc.200600110
    [Crossref], [PubMed], [CAS], Google Scholar
    20
    Asymmetry induction by cooperative intermolecular hydrogen bonds in surface-anchored layers of achiral molecules
    Dmitriev, Alexandre; Spillmann, Hannes; Stepanow, Sebastian; Strunskus, Thomas; Woell, Christof; Seitsonen, Ari P.; Lingenfelder, Magali; Lin, Nian; Barth, Johannes V.; Kern, Klaus
    ChemPhysChem (2006), 7 (10), 2197-2204CODEN: CPCHFT; ISSN:1439-4235. (Wiley-VCH Verlag GmbH & Co. KGaA)
    The meso-scale induction of two-dimensional supramol. chirality (formation of 2D org. domains with a single handedness) was achieved by self-assembly of 1,2,4-benzenetricarboxylic (trimellitic) acid on a Cu(100) surface at elevated temps. The combination of spectroscopic [XPS and near-edge X-ray absorption fine structure (NEXAFS)], real-space-probe [scanning tunneling microscopy (STM)], and computational [d. functional theory (DFT)] methods allows a comprehensive characterization of the obtained org. ad-layers, where details of mol. adsorption geometry, ir termol. coupling, and surface chem. bonding are elucidated. The trimellitic acid species, comprising three functional carboxylic groups, form distinct stable mirror-sym. hydrogen-bonded domains. The chiral ordering is assocd. with conformational restriction in the domains: mols. anchor to the substrate with an ortho carboxylate group, providing two para carboxylic acid moieties for collective lateral interweaving through H bonding, which induces a specific tilt of the mol. plane. The ease of mol. symmetry switching in domain formation makes homochiral-signature propagation solely limited by the terrace width. The mol. layer modifies the morphol. of the underlying copper substrate and induces μm-sized strictly homochiral terraces.
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  21. 21
    Borca, B.; Schendel, V.; Pétuya, R.; Pentegov, I.; Michnowicz, T.; Kraft, U.; Klauk, H.; Arnau, A.; Wahl, P.; Schlickum, U.; Kern, K. Bipolar Conductance Switching of Single Anthradithiophene Molecules. ACS Nano 2015, 9, 12506– 12512,  DOI: 10.1021/acsnano.5b06000
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    21
    Bipolar Conductance Switching of Single Anthradithiophene Molecules
    Borca, Bogdana; Schendel, Verena; Petuya, Remi; Pentegov, Ivan; Michnowicz, Tomasz; Kraft, Ulrike; Klauk, Hagen; Arnau, Andres; Wahl, Peter; Schlickum, Uta; Kern, Klaus
    ACS Nano (2015), 9 (12), 12506-12512CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    Single mol. switches are basic device elements in org. electronics. The pentacene analog anthradithiophene (ADT) shows a fully reversible binary switching between different adsorption conformations on a metallic surface accompanied by a charge transfer. These transitions are activated locally in single mols. in a low-temp. scanning tunneling microscope. The switching induces changes between bistable orbital structures and energy level alignment at the interface. The most stable geometry, the off state, which all mols. adopt upon evapn., corresponds to a short adsorption distance at which the electronic interactions of the acene rings bend the central part of the mol. toward the surface accompanied by a significant charge transfer from the metallic surface to the ADT mols. This leads to a shift of the LUMO down to the Fermi level (EF). In the on state the mol. has a flat geometry at a larger distance from the surface; consequently the interaction is weaker, resulting in a negligible charge transfer with an orbital structure resembling the HOMO when imaged close to EF. The potential barrier between these two states can be overcome reversibly by injecting charge carriers locally into individual mols. Voltage-controlled current traces show a hysteresis characteristic of a bipolar switching behavior. The interpretation is supported by 1st-principles calcns.
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  22. 22
    Liu, W.; Schuler, B.; Xu, Y.; Moll, N.; Meyer, G.; Gross, L.; Tkatchenko, A. Identical Binding Energies and Work Functions for Distinct Adsorption Structures: Olympicenes on the Cu(111) Surface. J. Phys. Chem. Lett. 2016, 7, 1022– 1027,  DOI: 10.1021/acs.jpclett.6b00223
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    22
    Identical Binding Energies and Work Functions for Distinct Adsorption Structures: Olympicenes on the Cu(111) Surface
    Liu, Wei; Schuler, Bruno; Xu, Yong; Moll, Nikolaj; Meyer, Gerhard; Gross, Leo; Tkatchenko, Alexandre
    Journal of Physical Chemistry Letters (2016), 7 (6), 1022-1027CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
    Ab initio calcns. with van der Waals interactions are used in combination with at. force microscopy expts. to explore the interaction mechanism for three structurally related olympicene mols. adsorbed on the Cu(111) surface. The substitution of a single atom in the olympicene mol. switches the nature of adsorption from predominantly physisorptive character [olympicene on Cu(111)], to an intermediate state [olympicene-derived ketone on Cu(111)], then to chemisorptive character [olympicene radical on Cu(111)]. Despite the remarkable difference in adsorption structures (by up to 0.9 Å in adsorption height) and different nature of bonding, the olympicene, its ketone, and its radical derivs. have essentially identical binding energies and work functions upon interaction with the metal substrate. These findings suggest that the stability and work functions of mol. adsorbates could be rendered insensitive to their adsorption structures, which could be a useful property for (opto)electronic applications.
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  23. 23
    Su, G.; Yang, S.; Li, S.; Butch, C. J.; Filimonov, S. N.; Ren, J. C.; Liu, W. Switchable Schottky Contacts: Simultaneously Enhanced Output Current and Reduced Leakage Current. J. Am. Chem. Soc. 2019, 141, 1628– 1635,  DOI: 10.1021/jacs.8b11459
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    23
    Switchable Schottky Contacts: Simultaneously Enhanced Output Current and Reduced Leakage Current
    Su, Guirong; Yang, Sha; Li, Shuang; Butch, Christopher J.; Filimonov, Sergey N.; Ren, Ji-Chang; Liu, Wei
    Journal of the American Chemical Society (2019), 141 (4), 1628-1635CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    Metal-semiconductor contacts are key components of nanoelectronics and at.-scale integrated circuits. In these components Schottky diodes provide a low forward voltage and a very fast switching rate but suffer the drawback of a high reverse leakage current. Improvement of the reverse bias characteristics without degrading performance of the diode at pos. voltages is deemed phys. impossible for conventional silicon-based Schottky diodes. However, in this work we propose that this design challenge can be overcome in the org.-based diodes by utilizing reversible transitions between distinct adsorption states of org. mols. on metal surfaces. Motivated by previous exptl. observations of controllable adsorption conformations of anthradithiophene on Cu(111), herein we use d. functional theory simulations to demonstrate the distinct Schottky barrier heights of the two adsorption states. The higher Schottky barrier of the reverse bias induced by a chemisorbed state results in low leakage current, while the lower barrier of the forward bias induced by a physisorbed state yields a larger output current. The rectifying behaviors are further supported by nonequil. Green's function transport calcns.
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  24. 24
    Paßens, M.; Caciuc, V.; Atodiresei, N.; Feuerbacher, M.; Moors, M.; Dunin-Borkowski, R. E.; Blügel, S.; Waser, R.; Karthäu-ser, S. Interface-Driven Formation of a Two-Dimensional Dodecag-onal Fullerene Quasicrystal. Nat. Commun. 2017, 8, 15367,  DOI: 10.1038/ncomms15367
    [Crossref], [PubMed], [CAS], Google Scholar
    24
    Interface-driven formation of a two-dimensional dodecagonal fullerene quasicrystal
    Passens, M.; Caciuc, V.; Atodiresei, N.; Feuerbacher, M.; Moors, M.; Dunin-Borkowski, R. E.; Bluegel, S.; Waser, R.; Karthaeuser, S.
    Nature Communications (2017), 8 (), 15367CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
    Since their discovery, quasicrystals have attracted continuous research interest due to their unique structural and phys. properties. Recently, it was demonstrated that dodecagonal quasicrystals could be used as bandgap materials in next-generation photonic devices. However, a full understanding of the formation mechanism of quasicrystals is necessary to control their phys. properties. Here we report the formation of a two-dimensional dodecagonal fullerene quasicrystal on a Pt3Ti(111) surface, which can be described in terms of a square-triangle tiling. Employing d. functional theory calcns., we identify the complex adsorption energy landscape of the Pt-terminated Pt3Ti surface that is responsible for the quasicrystal formation. We demonstrate the presence of quasicrystal-specific phason strain, which provides the degree of freedom required to accommodate the quasicryst. structure on the periodic substrate. Our results reveal detailed insight into an interface-driven formation mechanism and open the way to the creation of tailored fullerene quasicrystals with specific phys. properties.
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  25. 25
    Kakudate, T.; Tsukamoto, S.; Kubo, O.; Nakaya, M.; Nakaya-ma, T. Electronic Structures of Quaterthiophene and Septithiophene on Cu (111): Spatial Distribution of Adsorption-Induced States Studied by STM and DFT Calculation. J. Phys. Chem. C 2016, 120, 6681– 6688,  DOI: 10.1021/acs.jpcc.6b00566
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    25
    Electronic Structures of Quaterthiophene and Septithiophene on Cu(111): Spatial Distribution of Adsorption-Induced States Studied by STM and DFT Calculation
    Kakudate, Toshiyuki; Tsukamoto, Shigeru; Kubo, Osamu; Nakaya, Masato; Nakayama, Tomonobu
    Journal of Physical Chemistry C (2016), 120 (12), 6681-6688CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
    Quaterthiophene (4T) and septithiophene (7T) mols. adsorbed on Cu(111) surfaces have been studied by scanning tunneling microscopy and spectroscopy (STM and STS) at room temp. Both oligothiophene mols. formed one-dimensional (1D) chain structures on Cu(111), and each mol. in the 1D structures was obsd. as a row of bright ovals corresponding to thiophene units. Obsd. features of 4T and 7T mols. differed from those expected from the HOMO and LUMO of the free-standing mols., and d.-functional calcns. of a 4T mol. together with a Cu(111) surface reproduce the exptl. STM images as they reflected characteristic spatial distribution of adsorption-induced states. In other words, the adsorption-induced states were spatially protruding out from the mol. and not completely localized in the space between the mol. and the Cu(111) surface.
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  26. 26
    Schiffrin, A.; Capsoni, M.; Farahi, G.; Wang, C.-G.; Krull, C.; Castelli, M.; Roussy, T.; Cochrane, K. A.; Yin, Y.; Medhekar, N. V.; Fuhrer, M.; Shaw, A. Q.; Ji, W.; Burke, S. A. Designing Optoelectronic Properties by On-Surface Synthesis: Formation and Electronic Structure of an Iron–Terpyridine Macromolecular Complex. ACS Nano 2018, 12, 6545– 6553,  DOI: 10.1021/acsnano.8b01026
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    26
    Designing Optoelectronic Properties by On-Surface Synthesis: Formation and Electronic Structure of an Iron-Terpyridine Macromolecular Complex
    Schiffrin, Agustin; Capsoni, Martina; Farahi, Gelareh; Wang, Chen-Guang; Krull, Cornelius; Castelli, Marina; Roussy, Tanya; Cochrane, Katherine A.; Yin, Yuefeng; Medhekar, Nikhil V.; Fuhrer, Michael; Shaw, Adam Q.; Ji, Wei; Burke, Sarah A.
    ACS Nano (2018), 12 (7), 6545-6553CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    Supramol. chem. protocols applied on surfaces offer compelling avenues for at.-scale control over org.-inorg. interface structures. In this approach, adsorbate-surface interactions and two-dimensional confinement can lead to morphologies and properties that differ dramatically from those achieved via conventional synthetic approaches. Here, we describe the bottom-up, on-surface synthesis of one-dimensional coordination nanostructures based on an iron (Fe)-terpyridine (tpy) interaction borrowed from functional metal-org. complexes used in photovoltaic and catalytic applications. Thermally activated diffusion of sequentially deposited ligands and metal atoms and intraligand conformational changes lead to Fe-tpy coordination and formation of these nanochains. We used low-temp. scanning tunneling microscopy and d. functional theory to elucidate the at.-scale morphol. of the system, suggesting a linear tri-Fe linkage between facing, coplanar tpy groups. Scanning tunneling spectroscopy reveals the highest occupied orbitals, with dominant contributions from states located at the Fe node, and ligand states that mostly contribute to the lowest unoccupied orbitals. This electronic structure yields potential for hosting photoinduced metal-to-ligand charge transfer in the visible/near-IR. The formation of this unusual tpy/tri-Fe/tpy coordination motif has not been obsd. for wet chem. synthetic methods and is mediated by the bottom-up on-surface approach used here, offering pathways to engineer the optoelectronic properties and reactivity of metal-org. nanostructures.
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  27. 27
    Gutzler, R.; Garg, M.; Ast, Ch. R.; Kuhnke, K.; Kern, K. Light–Matter Interaction at Atomic Scales. Nat. Rev. Phys. 2021, 3, 441– 453,  DOI: 10.1038/s42254-021-00306-5
    [Crossref], Google Scholar
    There is no corresponding record for this reference.
  28. 28
    Rossel, F.; Pivetta, M.; Schneider, W.-D. Luminescence Experiments on Supported Molecules with the Scanning Tunneling Microscope. Surf. Sci. Rep. 2010, 65, 129– 144,  DOI: 10.1016/j.surfrep.2010.06.001
    [Crossref], [CAS], Google Scholar
    28
    Luminescence experiments on supported molecules with the scanning tunneling microscope
    Rossel, Frederic; Pivetta, Marina; Schneider, Wolf-Dieter
    Surface Science Reports (2010), 65 (5), 129-144CODEN: SSREDI; ISSN:0167-5729. (Elsevier B.V.)
    The present review on light emission stimulated by electrons tunneling inelastically through a junction formed by a sample and a tip of a scanning tunneling microscope (STM) focusses on the most relevant results obtained for a variety of systems, including metal surfaces, single mols. on ultrathin dielec. films, and mols. assembled in thin films or in nanostructures on metal surfaces or on dielec. films. The decisive role of the localized surface plasmon for the enhanced luminescence from supported mols. is highlighted. The progress so far achieved for both exptl. techniques and theor. anal. is addressed. Current trends are discussed and possible future developments are indicated. STM-induced photon emission has come a long way. More than a decade ago, simple photon maps reflected only the emitted light intensity on a local scale. Today this technique has advanced to spectroscopically resolve optical emission from electronic and vibrational mol. modes in single mols., demonstrating the capability of STM-induced light emission for chem. recognition on the single-mol. scale.
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  29. 29
    Kumar, D.; Hellerstedt, J.; Field, B.; Lowe, B.; Yin, Y.; Medhekar, N. V.; Schiffrin, A. Manifestation of Strongly Correlated Electrons in a 2D Kagome Metal–Organic Framework. Adv. Funct. Mater. 2021, 31, 2106474,  DOI: 10.1002/adfm.202106474
    [Crossref], [CAS], Google Scholar
    29
    Manifestation of Strongly Correlated Electrons in a 2D Kagome Metal-Organic Framework
    Kumar, Dhaneesh; Hellerstedt, Jack; Field, Bernard; Lowe, Benjamin; Yin, Yuefeng; Medhekar, Nikhil V.; Schiffrin, Agustin
    Advanced Functional Materials (2021), 31 (48), 2106474CODEN: AFMDC6; ISSN:1616-301X. (Wiley-VCH Verlag GmbH & Co. KGaA)
    2D and layered electronic materials characterized by a kagome lattice, whose valence band structure includes two Dirac bands and one flat band, can host a wide range of tunable topol. and strongly correlated electronic phases. While strong electron correlations have been obsd. in inorg. kagome crystals, they remain elusive in org. systems, which benefit from versatile synthesis protocols via mol. self-assembly and metal-ligand coordination. Here, direct exptl. evidence of local magnetic moments resulting from strong electron-electron Coulomb interactions in a 2D metal-org. framework (MOF) is reported. The latter consists of di-cyano-anthracene (DCA) mols. arranged in a kagome structure via coordination with copper (Cu) atoms on a silver surface [Ag(111)]. Temp.-dependent scanning tunneling spectroscopy reveals magnetic moments spatially confined to DCA and Cu sites of the MOF, and Kondo screened by the Ag(111) conduction electrons. By d. functional theory and mean-field Hubbard modeling, it is shown that these magnetic moments are the direct consequence of strong Coulomb interactions between electrons within the kagome MOF. The findings pave the way for nanoelectronics and spintronics technologies based on controllable correlated electron phases in 2D org. materials.
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  30. 30
    Garnica, M.; Stradi, D.; Calleja, F.; Barja, S.; Díaz, C.; Alcamí, M.; Arnau, A.; Vázquez de Parga, A. L.; Martín, F.; Miranda, R. Probing the Site-Dependent Kondo Response of Nanostructured Graphene with Organic Molecules. Nano Lett. 2014, 14, 4560– 4567,  DOI: 10.1021/nl501584v
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    30
    Probing the Site-Dependent Kondo Response of Nanostructured Graphene with Organic Molecules
    Garnica, Manuela; Stradi, Daniele; Calleja, Fabian; Barja, Sara; Diaz, Cristina; Alcami, Manuel; Arnau, Andres; Vazquez de Parga, Amadeo L.; Martin, Fernando; Miranda, Rodolfo
    Nano Letters (2014), 14 (8), 4560-4567CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
    TCNQ mols. were used as a sensitive probe for the Kondo response of the electron gas of a nanostructured graphene grown on Ru(0001) presenting a moir´e pattern. All adsorbed mols. acquired an extra electron by charge transfer from the substrate, but only those adsorbed in the FCC-Top areas of the moir´e show magnetic moment and Kondo resonance in the STS spectra. DFT calcns. trace this behavior to the existence of a surface resonance in the low areas of the graphene moir´e, whose d. distribution strongly depends on the stacking sequence of the moir´e area and effectively quenches the magnetic moment for HCP-Top sites.
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  31. 31
    Carbone, C.; Gardonio, S.; Moras, P.; Lounis, S.; Heide, M.; Bihlmayer, G.; Atodiresei, N.; Dederichs, P. H.; Blügel, S.; Vlaic, S.; Lehnert, A.; Ouazi, S.; Rusponi, S.; Brune, H.; Honolka, J.; Enders, A.; Kern, K.; Stepanow, S.; Krull, C.; Balashov, T.; Mugarza, A.; Gambardella, P. Self-Assembled Nanometer-Scale Magnetic Networks on Surfaces: Fundamental Interactions and Functional Properties. Adv. Funct. Mater. 2011, 21, 1212– 1228,  DOI: 10.1002/adfm.201001325
    [Crossref], [CAS], Google Scholar
    31
    Self-Assembled Nanometer-Scale Magnetic Networks on Surfaces: Fundamental Interactions and Functional Properties
    Carbone, Carlo; Gardonio, Sandra; Moras, Paolo; Lounis, Samir; Heide, Marcus; Bihlmayer, Gustav; Atodiresei, Nicolae; Dederichs, Peter Heinz; Bluegel, Stefan; Vlaic, Sergio; Lehnert, Anne; Ouazi, Safia; Rusponi, Stefano; Brune, Harald; Honolka, Jan; Enders, Axel; Kern, Klaus; Stepanow, Sebastian; Krull, Cornelius; Balashov, Timofey; Mugarza, Aitor; Gambardella, Pietro
    Advanced Functional Materials (2011), 21 (7), 1212-1228CODEN: AFMDC6; ISSN:1616-301X. (Wiley-VCH Verlag GmbH & Co. KGaA)
    A review. Nanomagnets of controlled size, organized into regular patterns open new perspectives in the fields of nanoelectronics, spintronics, and quantum computation. Self-assembling processes on various types of substrates allow designing fine-structured architectures and tuning of their magnetic properties. Here, starting from a description of fundamental magnetic interactions at the nanoscale, we review recent exptl. approaches to fabricate zero-, one-, and two-dimensional magnetic particle arrays with dimensions reduced to the at. limit and unprecedented areal d. We describe systems composed of individual magnetic atoms, metal-org. networks, metal wires, and bimetallic particles, as well as strategies to control their magnetic moment, anisotropy, and temp.-dependent magnetic behavior. The investigation of self-assembled subnanometer magnetic particles leads to significant progress in the design of fundamental and functional aspects, mutual interactions among the magnetic units, and their coupling with the environment.
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  32. 32
    Xiong, M.; Gao, Z.; Qin, Y. Spillover in Heterogeneous Catalysis: New Insights and Opportunities. ACS Catal. 2021, 11, 3159– 3172,  DOI: 10.1021/acscatal.0c05567
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    32
    Spillover in Heterogeneous Catalysis: New Insights and Opportunities
    Xiong, Mi; Gao, Zhe; Qin, Yong
    ACS Catalysis (2021), 11 (5), 3159-3172CODEN: ACCACS; ISSN:2155-5435. (American Chemical Society)
    A review. Spillover is a well-known phenomenon in heterogeneous catalysis and is involved in many important reactions. The establishment of the spillover concept opened up a new research field for an in-depth understanding of the dynamic behavior of migrated species on a catalyst surface. However, a comprehensive understanding of spillover remains lacking. In recent years, the development of advanced characterization techniques in combination with well-controlled synthesis methodologies has provided us with increasing worthwhile information about spillover. This Review mainly describes recent progress on the characterization and mechanism of hydrogen spillover and how to effectively utilize the spillover effect for enhanced catalytic performance. Addnl., the challenges remaining in this research area are discussed, and possible research directions for the future are proposed.
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  33. 33
    Nørskov, J. K.; Studt, F.; Abild-Pedersen, F.; Bligaard, T. Fundamental Concepts in Heterogeneous Catalysis; John Wiley & Sons, Inc.: Hoboken, NJ, 2014.  DOI: 10.1002/9781118892114 .
    [Crossref], Google Scholar
    There is no corresponding record for this reference.
  34. 34
    Samantaray, M. K.; D’Elia, V.; Pump, E.; Falivene, L.; Harb, M.; Ould Chikh, S.; Cavallo, L.; Basset, J.-M. The Comparison between Single Atom Catalysis and Surface Organometallic Catalysis. Chem. Rev. 2020, 120, 734– 813,  DOI: 10.1021/acs.chemrev.9b00238
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    34
    The Comparison between Single Atom Catalysis and Surface Organometallic Catalysis
    Samantaray, Manoja K.; D'Elia, Valerio; Pump, Eva; Falivene, Laura; Harb, Moussab; Ould Chikh, Samy; Cavallo, Luigi; Basset, Jean-Marie
    Chemical Reviews (Washington, DC, United States) (2020), 120 (2), 734-813CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
    A review. Single atom catalysis (SAC) is a recent discipline of heterogeneous catalysis for which a single atom on a surface is able to carry out various catalytic reactions. A kind of revolution in heterogeneous catalysis by metals for which it was assumed that specific sites or defects of a nanoparticle were necessary to activate substrates in catalytic reactions. In another extreme of the spectrum, surface organometallic chem. (SOMC), and, by extension, surface organometallic catalysis (SOMCat), have demonstrated that single atoms on a surface, but this time with specific ligands, could lead to a more predictive approach in heterogeneous catalysis. The predictive character of SOMCat was just the result of intuitive mechanisms derived from the elementary steps of mol. chem. This review article will compare the aspects of single atom catalysis and surface organometallic catalysis by considering several specific catalytic reactions, some of which exist for both fields, whereas others might see mutual overlap in the future. After a definition of both domains, a detailed approach of the methods, mostly modeling and spectroscopy, will be followed by a detailed anal. of catalytic reactions: hydrogenation, dehydrogenation, hydrogenolysis, oxidative dehydrogenation, alkane and cycloalkane metathesis, methane activation, metathetic oxidn., CO2 activation to cyclic carbonates, imine metathesis, and selective catalytic redn. (SCR) reactions. A prospective resulting from present knowledge is showing the emergence of a new discipline from the overlap between the two areas.
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  35. 35
    Fox, E. B.; Liu, Z.-W.; Liu, Z.-T. Ultraclean Fuels Production and Utilization for the Twenty-First Century: Advances toward Sustainable Transportation Fuels. Energy Fuels 2013, 27, 6335– 6338,  DOI: 10.1021/ef401094t
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    35
    Ultraclean Fuels Production and Utilization for the Twenty-First Century: Advances toward Sustainable Transportation Fuels
    Fox, Elise B.; Liu, Zhong-Wen; Liu, Zhao-Tie
    Energy & Fuels (2013), 27 (11), 6335-6338CODEN: ENFUEM; ISSN:0887-0624. (American Chemical Society)
    A review. Ultraclean fuels prodn. has become increasingly important as a method to help decrease emissions and allow for the introduction of alternative feedstocks for transportation fuels. Established methods, such as Fischer-Tropsch, have seen a resurgence of interest as natural gas prices drop and existing petroleum resources require more intensive cleanup and purifn. to meet stringent environmental stds. This review covers some of the advances in deep desulfurization and synthesis gas conversion into fuels and feedstocks that were presented at the 245th American Chem. Society (ACS) Spring Annual Meeting in New Orleans, LA, in the Division of Energy and Fuels symposium on "Ultraclean Fuels Prodn. and Utilization".
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  36. 36
    Saha, B.; Vedachalam, S.; Dalai, A. K. Review on Recent Advances in Adsorptive Desulfurization. Fuel Process. Technol. 2021, 214, 106685,  DOI: 10.1016/j.fuproc.2020.106685
    [Crossref], [CAS], Google Scholar
    36
    Review on recent advances in adsorptive desulfurization
    Saha, Biswajit; Vedachalam, Sundaramurthy; Dalai, Ajay K.
    Fuel Processing Technology (2021), 214 (), 106685CODEN: FPTEDY; ISSN:0378-3820. (Elsevier Ltd.)
    A review. The challenges of hydrodesulfurization for desulfurizing the refractory sulfur compds. of petroleum fuels are prompting researchers to investigate the different non-conventional desulfurization techniques. Adsorptive desulfurization (ADS) is emerging as a low-cost alternative to ultra-deep hydrodesulfurization. In ADS, sulfur compds. are removed via physicochem. adsorption using a selective adsorbent. This review focuses on the latest development in ADS. Zeolite, metal oxide, metal-org. framework, mesoporous material, and carbon are assessed for desulfurization of the model and real feedstocks. The ADS performance of these materials can be improved by incorporating metals. Recent progress on improving the selectivity, stability, reusability is discussed. Depending on adsorbent surface chem. compn., sulfur mols. are removed through π complexation, acid-base, metal-sulfur, and Van der Waals forces. The effects of process parameters, thermodn., and kinetics of ADS are also discussed. Selectivity is found to be a key challenge in ADS of real feedstocks due to competitive adsorption. The testing of adsorbents with real fuels is crucial for the commercialization of ADS. Developments of robust adsorbent with less expensive metals and ideal regeneration methods are needed to demonstrate the capabilities of ADS com. The search for a low-cost, and efficient ADS adsorbent is ongoing, and currently, its industrial adaptation is extremely limited.
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  37. 37
    Yang, R. T.; Hernández-Maldonado, A. J.; Yang, F. H. Desulfurization of Transportation Fuels with Zeolites Under Ambient Conditions. Science 2003, 301, 79– 81,  DOI: 10.1126/science.1085088
    [Crossref], [PubMed], [CAS], Google Scholar
    37
    Desulfurization of Transportation Fuels with Zeolites Under Ambient Conditions
    Yang, Ralph T.; Hernandez-Maldonado, Arturo J.; Yang, Frances H.
    Science (Washington, DC, United States) (2003), 301 (5629), 79-81CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
    Deep desulfurization of transportation fuels (gasoline, diesel, and jet fuels) is being mandated by U.S. and foreign governments and is also needed for future fuel cell applications. However, it is extremely difficult and costly to achieve with current technol., which requires catalytic reactors operated at high pressure and temp. We show that Cu+ and Ag+ zeolite Y can adsorb sulfur compds. from com. fuels selectively and with high sulfur capacities (by π complexation) at ambient temp. and pressure. Thus, the sulfur content was reduced from 430 to <0.2 ppm by wt. in a com. diesel at a sorbent capacity of 34 cubic centimeters of clean diesel produced per g of sorbent. This sulfur selectivity and capacity are orders of magnitude higher than those obtained by previously known sorbents.
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  38. 38
    Borca, B.; Michnowicz, T.; Pétuya, R.; Pristl, M.; Schendel, V.; Pentegov, I.; Kraft, U.; Klauk, H.; Wahl, P.; Gutzler, R.; Arnau, A.; Schlickum, U.; Kern, K. Electric-Field-Driven Direct Desulfurization. ACS Nano 2017, 11, 4703– 4709,  DOI: 10.1021/acsnano.7b00612
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    38
    Electric-Field-Driven Direct Desulfurization
    Borca, Bogdana; Michnowicz, Tomasz; Petuya, Remi; Pristl, Marcel; Schendel, Verena; Pentegov, Ivan; Kraft, Ulrike; Klauk, Hagen; Wahl, Peter; Gutzler, Rico; Arnau, Andres; Schlickum, Uta; Kern, Klaus
    ACS Nano (2017), 11 (5), 4703-4709CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    The ability to elucidate the elementary steps of a chem. reaction at the at. scale is important for the detailed understanding of the processes involved, which is key to uncover avenues for improved reaction paths. Here, we track the chem. pathway of an irreversible direct desulfurization reaction of tetracenothiophene adsorbed on the Cu(111) closed-packed surface at the submol. level. Using the precise control of the tip position in a scanning tunneling microscope and the elec. field applied across the tunnel junction, the two carbon-sulfur bonds of a thiophene unit are successively cleaved. Comparison of spatially mapped mol. states close to the Fermi level of the metallic substrate acquired at each reaction step with d. functional theory calcns. reveals the two elementary steps of this reaction mechanism. The first reaction step is activated by an elec. field larger than 2 V nm-1, practically in absence of tunneling electrons, opening the thiophene ring and leading to a transient intermediate. Subsequently, at the same threshold elec. field and with simultaneous injection of electrons into the mol., the exergonic detachment of the sulfur atom is triggered. Thus, a stable mol. with a bifurcated end is obtained, which is covalently bound to the metallic surface. The sulfur atom is expelled from the vicinity of the mol.
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  39. 39
    Michnowicz, T.; Borca, B.; Pétuya, R.; Schendel, V.; Pristl, M.; Pentegov, I.; Kraft, U.; Klauk, H.; Wahl, P.; Mutombo, P.; Jelínek, P.; Arnau, A.; Schlickum, U.; Kern, K. Controlling Single Molecule Conductance by a Locally Induced Chemical Reaction on Individual Thiophene Units. Angew. Chem. Int. . Ed. 2020, 59, 6207– 6212,  DOI: 10.1002/anie.201915200
    [Crossref], [CAS], Google Scholar
    39
    Controlling Single Molecule Conductance by a Locally Induced Chemical Reaction on Individual Thiophene Units
    Michnowicz, Tomasz; Borca, Bogdana; Petuya, Remi; Schendel, Verena; Pristl, Marcel; Pentegov, Ivan; Kraft, Ulrike; Klauk, Hagen; Wahl, Peter; Mutombo, Pingo; Jelinek, Pavel; Arnau, Andres; Schlickum, Uta; Kern, Klaus
    Angewandte Chemie, International Edition (2020), 59 (15), 6207-6212CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)
    Among the prerequisites for the progress of single-mol.-based electronic devices are a better understanding of the electronic properties at the individual mol. level and the development of methods to tune the charge transport through mol. junctions. Scanning tunneling microscopy (STM) is an ideal tool not only for the characterization, but also for the manipulation of single atoms and mols. on surfaces. The conductance through a single mol. can be measured by contacting the mol. with at. precision and forming a mol. bridge between the metallic STM tip electrode and the metallic surface electrode. The parameters affecting the conductance are mainly related to their electronic structure and to the coupling to the metallic electrodes. Here, the exptl. and theor. analyses are focused on single tetracenothiophene mols. and demonstrate that an in situ-induced direct desulfurization reaction of the thiophene moiety strongly improves the mol. anchoring by forming covalent bonds between mol. carbon and copper surface atoms. This bond formation leads to an increase of the conductance by about 50 % compared to the initial state.
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  40. 40
    Ohmann, R.; Levita, G.; Vitali, L.; De Vita, A.; Kern, K. Influence of Subsurface Layers on the Adsorption of Large Organic Molecules on Close-Packed Metal Surfaces. ACS Nano 2011, 5, 1360– 1365,  DOI: 10.1021/nn103058e
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    40
    Influence of Subsurface Layers on the Adsorption of Large Organic Molecules on Close-Packed Metal Surfaces
    Ohmann, Robin; Levita, Giacomo; Vitali, Lucia; De Vita, Alessandro; Kern, Klaus
    ACS Nano (2011), 5 (2), 1360-1365CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
    The asym. mol. 4-[trans-2-(pyrid-4-yl-vinyl)] benzoic acid (PVBA) adsorbed on Cu(111) is characterized by scanning tunneling microscopy (STM) and d. functional theory (DFT) to det. the influence of subsurface at. layers on the adsorption. In contrast to the 6-fold symmetry of the 1st at. layer of close-packed surfaces, the arrangement of the isolated mols. follows predominantly a 3-fold symmetry. This redn. in symmetry, where the mol. selects a specific orientation along the -211 axes, reveals the contribution of lower-lying Cu layers to the mol. arrangement. The calcns. rationalize the interaction of the substrate with the mol. in terms of electrostatic screening and local relaxation phenomena.
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  41. 41
    Lagoute, J.; Kanisawa, K.; Fölsch, S. Manipulation and Adsorption-Site Mapping of Single Pentacene Molecules on Cu (111). Phys. Rev. B 2004, 70, 245415,  DOI: 10.1103/PhysRevB.70.245415
    [Crossref], [CAS], Google Scholar
    41
    Manipulation and adsorption-site mapping of single pentacene molecules on Cu(111)
    Lagoute, Jerome; Kanisawa, Kiyoshi; Folsch, Stefan
    Physical Review B: Condensed Matter and Materials Physics (2004), 70 (24), 245415/1-245415/6CODEN: PRBMDO; ISSN:1098-0121. (American Physical Society)
    Low-temp. scanning tunneling microscopy at 7 K is used to study the adsorption and manipulation of single pentacene mols. on Cu(111). Controlled lateral translations of the mol. are performed along different high-symmetry directions of the substrate via attractive tip-mol. interactions. By a detailed site-mapping technique combining lateral manipulations of the mol. and of native substrate adatoms the authors det. the adsorptive configuration of the arom. mol. The authors find a planar adsorption geometry with the long mol. axis aligned with the close-packed Cu atom rows and the benzene units centered over hcp. hollow sites of the substrate.
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  42. 42
    Toyoda, K.; Nakano, Y.; Hamada, I.; Lee, K.; Yanagisawa, S.; Morikawa, Y. 2009. First-Principles Study of the Pentacene/Cu (111) Interface: Adsorption States and Vacuum Level Shifts. J. Electron Spectrosc. 2009, 174, 78– 84,  DOI: 10.1016/j.elspec.2009.04.005
    [Crossref], [CAS], Google Scholar
    42
    First-principles study of the pentacene/Cu(111) interface. Adsorption states and vacuum level shifts
    Toyoda, Kenji; Nakano, Yosuke; Hamada, Ikutaro; Lee, Kyuho; Yanagisawa, Susumu; Morikawa, Yoshitada
    Journal of Electron Spectroscopy and Related Phenomena (2009), 174 (1-3), 78-84CODEN: JESRAW; ISSN:0368-2048. (Elsevier B.V.)
    We have studied the interaction of pentacene with a Cu(1 1 1) surface using d. functional theory (DFT) within a generalized gradient approxn. (GGA) and the van der Waals d. functional. The adsorption energy is accurately predicted by vdW-DF, while the equil. distances between pentacene and the metal substrate (Z C) are overestimated by both GGA and vdW-DF. The work function changes depend significantly on Z C. The exptl. work function change can be successfully reproduced by GGA if the exptl. reported adsorption geometry is used, whereas the magnitude of the work function change is underestimated if calcd. adsorption geometries are applied. We examd. the IDIS model to compare it with the GGA results. The interface dipoles estd. by the IDIS model fairly agree with the GGA results, provided that the adsorption distance is large. On the other hand, they tend to deviate from the GGA results as the adsorption distance becomes smaller, where back donation from the metal surface to the adsorbate occurs. At exptl. reported metal-org. distance, back donation is significant enough to induce polarization of pentacene mols. perpendicular to the surface, which leads to a redn. of the work function. Thus, at the exptl. reported metal-org. distance, the work function change estd. by a simple IDIS model deviates from that calcd. by self-consistent GGA calcns. At the exptl. reported metal-org. distance, the transferred electrons create weak chem. bonds between pentacene and the Cu(1 1 1) surface, illustrating the reactive nature of pentacene.
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  43. 43
    Hu, Z. X.; Lan, H.; Ji, W. Role of the Dispersion Force in Modeling the Interfacial Properties of Molecule-Metal Interfaces: Ad-sorption of Thiophene on Copper Surfaces. Sci. Rep. 2014, 4, 5036,  DOI: 10.1038/srep05036
    [Crossref], [PubMed], [CAS], Google Scholar
    43
    Role of the dispersion force in modeling the interfacial properties of molecule-metal interfaces: adsorption of thiophene on copper surfaces
    Hu, Zhi-Xin; Lan, Haiping; Ji, Wei
    Scientific Reports (2014), 4 (), 5036CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)
    We present d. functional theory calcns. of the geometry, adsorption energy and electronic structure of thiophene adsorbed on Cu(111), Cu(110) and Cu(100) surfaces. Our calcns. employ dispersion corrections and self-consistent van der Waals d. functionals (vdW-DFs). In terms of speed and accuracy, we find that the dispersion-energy-cor. Revised Perdue-Burke-Enzerhof (RPBE) functional is the "best balanced" method for predicting structural and energetic properties, while vdW-DF is also highly accurate if a proper exchange functional is used. Discrepancies between theory and expt. in mol. geometry can be solved by considering x-ray generated core-holes. However, the discrepancy concerning the adsorption site for thiophene/Cu(100) remains unresolved and requires both further expts. and deeper theor. anal. For all the interfaces, the PBE functional reveals a covalent bonding picture which the inclusion of dispersive contributions does not change to a vdW one. Our results provide a comprehensive understanding of the role of dispersive forces in modeling mol.-metal interfaces.
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  44. 44
    Lechner, B. A.; Sacchi, M.; Jardine, A. P.; Hedgeland, H.; Allison, W.; Ellis, J.; Jenkins, S. J.; Dastoor, P. C.; Hinch, B. J. (2013). Jumping, Rotating, and Flapping: The Atomic-Scale Motion of Thiophene on Cu (111). J. Phys. Chem. Lett. 2013, 4, 1953– 1958,  DOI: 10.1021/jz400639c
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    44
    Jumping, Rotating, and Flapping: The Atomic-Scale Motion of Thiophene on Cu(111)
    Lechner, Barbara A. J.; Sacchi, Marco; Jardine, Andrew P.; Hedgeland, Holly; Allison, William; Ellis, John; Jenkins, Stephen J.; Dastoor, Paul C.; Hinch, B. J.
    Journal of Physical Chemistry Letters (2013), 4 (11), 1953-1958CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
    The authors investigated the dynamics of isolated thiophene mols. on Cu(111) by combining helium spin-echo (HeSE) spectroscopy with d. functional theory calcns. The thiophene/Cu(111) system displays a rich array of aperiodic dynamical phenomena that include jump diffusion between adjacent atop sites over a 59-62 meV barrier and activated rotation around a sulfur-copper anchor, two processes that have been obsd. previously for related systems. In addn., the authors present exptl. evidence for a new, weakly activated process, the flapping of the mol. ring. Repulsive inter-adsorbate interactions and an exceptionally high friction coeff. of 5 ± 2 ps-1 were also obsd. These expts. demonstrate the versatility of the HeSE technique, and the quant. information extd. in a detailed anal. provides an ideal benchmark for state-of-the-art theor. techniques including nonlocal adsorbate-substrate interactions.
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  45. 45
    Kraft, U.; Anthony, J. E.; Ripaud, E.; Loth, M. A.; Weber, E.; Klauk, H. Low-Voltage Organic Transistors Based on Tetraceno[2,3-b]thiophene: Contact Resistance and Air Stability. Chem. Mater. 2015, 27, 998– 1004,  DOI: 10.1021/cm5043183
    [ACS Full Text ACS Full Text], [CAS], Google Scholar
    45
    Low-Voltage Organic Transistors Based on Tetraceno[2,3-b]thiophene: Contact Resistance and Air Stability
    Kraft, Ulrike; Anthony, John E.; Ripaud, Emilie; Loth, Marsha A.; Weber, Edwin; Klauk, Hagen
    Chemistry of Materials (2015), 27 (3), 998-1004CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
    The small-mol. org. semiconductor tetraceno[2,3-b]thiophene was synthesized through an environmentally friendly synthetic route, using NaBH4, rather than Al/HgCl2, for the redn. of the quinone. Low-voltage org. thin-film transistors (TFTs) were fabricated using tetraceno[2,3-b]thiophene and, for comparison, pentacene and anthradithiophene as the semiconductor. The tetraceno[2,3-b]thiophene TFTs have an effective field-effect mobility as large as 0.55 cm2 V-1 s-1 and a subthreshold swing of 0.13 V/decade. The contact resistance of the tetraceno[2,3-b]thiophene TFTs is substantially smaller than that of the anthradithiophene TFTs and similar to that of the pentacene TFTs. The long-term air stability of TFTs based on all three semiconductors was monitored over a period of 12 mo. The initial charge-carrier mobility of the tetraceno[2,3-b]thiophene TFTs is ∼50% smaller than that of the pentacene TFTs, but as a result of the greater ionization potential and better air stability induced by the terminal thiophene ring condensed at the thiophene-b-bond, the tetraceno[2,3-b]thiophene TFTs outperform the pentacene TFTs after continuous exposure to ambient air for just 3 mo.
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  46. 46
    Horcas, I.; Fernández, R.; Gómez-Rodríguez, J. M.; Colchero, J.; Gómez-Herrero, J.; Baró, A. M. WSXM: A Software for Scanning Probe Microscopy and a Tool for Nanotechnology. Rev. Sci. Instrum. 2007, 78, 013705,  DOI: 10.1063/1.2432410
    [Crossref], [PubMed], [CAS], Google Scholar
    46
    WSXM: a software for scanning probe microscopy and a tool for nanotechnology
    Horcas, I.; Fernandez, R.; Gomez-Rodriguez, J. M.; Colchero, J.; Gomez-Herrero, J.; Baro, A. M.
    Review of Scientific Instruments (2007), 78 (1), 013705/1-013705/8CODEN: RSINAK; ISSN:0034-6748. (American Institute of Physics)
    In this work we briefly describe the most relevant features of WSXM, a freeware scanning probe microscopy software based on MS-Windows. The article is structured in three different sections: The introduction is a perspective on the importance of software on scanning probe microscopy. The second section is devoted to describe the general structure of the application; in this section the capabilities of WSXM to read third party files are stressed. Finally, a detailed discussion of some relevant procedures of the software is carried out.
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  47. 47
    Berland, K.; Hyldgaard, P. Exchange Functional that Test the Robustness of the Plasmon Description of the van der Waals Density Functional. Phys. Rev. B 2014, 89, 035412,  DOI: 10.1103/PhysRevB.89.035412
    [Crossref], [CAS], Google Scholar
    47
    Exchange functional that tests the robustness of the plasmon description of the van der Waals density functional
    Berland, Kristian; Hyldgaard, Per
    Physical Review B: Condensed Matter and Materials Physics (2014), 89 (3), 035412/1-035412/8CODEN: PRBMDO; ISSN:1098-0121. (American Physical Society)
    Is the plasmon description within the nonlocal correlation of the van der Waals d. functional by Dion and coworkers (vdW-DF) robust enough to describe all exchange-correlation components. To address this question, we design an exchange functional based on this plasmon description as well as recent anal. on exchange in the large-s regime. In the regime with reduced gradients s = |.del.n|/2nkF(n) smaller than ≈2.5, dominating the nonlocal correlation part of the binding energy, the enhancement factor Fx(s) closely resembles the Langreth-Vosko screened exchange. In the s regime beyond, dominated by exchange, Fx(s) passes smoothly over to the revised Perdew-Wang-86 form. We term the specific exchange functional LV-PW86r, whereas the full van der Waals functional version emphasizing consistent handling of exchange is termed vdW-DF-cx. Our tests indicate that vdW-DF-cx produces accurate sepns. and binding energies of the S22 data set of mol. dimers as well as accurate lattice consts. and bulk moduli of layered materials and tightly bound solids. These results suggest that the plasmon description within vdW-DF gives a good description of both exchange and correlation effects in the low-to-moderae s regime.
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  48. 48
    Kresse, G.; Furthmüller, J. Efficiency of Ab-Initio Total Energy Calculations for Metals and Semiconductors using a Plane-Wave Basis Set. Comput. Mater. Sci. 1996, 6, 15,  DOI: 10.1016/0927-0256(96)00008-0
    [Crossref], [CAS], Google Scholar
    48
    Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
    Kresse, G.; Furthmuller, J.
    Computational Materials Science (1996), 6 (1), 15-50CODEN: CMMSEM; ISSN:0927-0256. (Elsevier)
    The authors present a detailed description and comparison of algorithms for performing ab-initio quantum-mech. calcns. using pseudopotentials and a plane-wave basis set. The authors will discuss: (a) partial occupancies within the framework of the linear tetrahedron method and the finite temp. d.-functional theory, (b) iterative methods for the diagonalization of the Kohn-Sham Hamiltonian and a discussion of an efficient iterative method based on the ideas of Pulay's residual minimization, which is close to an order N2atoms scaling even for relatively large systems, (c) efficient Broyden-like and Pulay-like mixing methods for the charge d. including a new special preconditioning optimized for a plane-wave basis set, (d) conjugate gradient methods for minimizing the electronic free energy with respect to all degrees of freedom simultaneously. The authors have implemented these algorithms within a powerful package called VAMP (Vienna ab-initio mol.-dynamics package). The program and the techniques have been used successfully for a large no. of different systems (liq. and amorphous semiconductors, liq. simple and transition metals, metallic and semi-conducting surfaces, phonons in simple metals, transition metals and semiconductors) and turned out to be very reliable.
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  49. 49
    Momma, K.; Izumi, F. VESTA: A Three-Dimensional Visualization System for Electronic and Structural Analysis. J. Appl. Crystallogr. 2008, 41, 653– 658,  DOI: 10.1107/S0021889808012016
    [Crossref], [CAS], Google Scholar
    49
    VESTA: a three-dimensional visualization system for electronic and structural analysis
    Momma, Koichi; Izumi, Fujio
    Journal of Applied Crystallography (2008), 41 (3), 653-658CODEN: JACGAR; ISSN:0021-8898. (International Union of Crystallography)
    A cross-platform program, VESTA, has been developed to visualize both structural and volumetric data in multiple windows with tabs. VESTA represents crystal structures by ball-and-stick, space-filling, polyhedral, wire frame, stick, dot-surface and thermal-ellipsoid models. A variety of crystal-chem. information is extractable from fractional coordinates, occupancies and oxidn. states of sites. Volumetric data such as electron and nuclear densities, Patterson functions, and wavefunctions are displayed as isosurfaces, bird's-eye views and two-dimensional maps. Isosurfaces can be colored according to other phys. quantities. Translucent isosurfaces and/or slices can be overlapped with a structural model. Collaboration with external programs enables the user to locate bonds and bond angles in the 'graphics area', simulate powder diffraction patterns, and calc. site potentials and Madelung energies. Electron densities detd. exptl. are convertible into their Laplacians and electronic energy densities.
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  1. Federico Mazzola, Yanxue Zhang, Natalia Olszowska, Marcin Rosmus, Gianluca D’Olimpio, Marian Cosmin Istrate, Grazia Giuseppina Politano, Ivana Vobornik, Raman Sankar, Corneliu Ghica, Junfeng Gao, Antonio Politano. Fermiology of Chiral Cadmium Diarsenide CdAs2, a Candidate for Hosting Kramers–Weyl Fermions. The Journal of Physical Chemistry Letters 2023, 14 (13) , 3120-3125. https://doi.org/10.1021/acs.jpclett.3c00005
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  • Abstract

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    Figure 1

    Figure 1. Tetracenothiophene (TCT) adsorption on Cu(111). (a) Molecular structure of TCT. (b) STM topography showing several TCT molecules adsorbed along the high-symmetry crystallographic directions of the Cu(111) surface. (c) Apparent height profile of a TCT molecule, with the highest side corresponding to the thiophene moiety.

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    Figure 2

    Figure 2. Preferential adsorption of TCT on Cu(111) and induced chirality. (a) Optimized adsorption geometry of TCT adsorption on the Cu(111) surface, revealing the favorable adsorption of the thiophene unit with the sulfur atom on top of a Cu atom and the acene rings on a hollow position, both the hollow-hcp and the hollow-fcc sites. (b) Relative adsorption energy difference between the two adsorption configurations, having the most stable arrangement on the hollow-hcp site. (c) Structural model of the TCT adsorption along one crystallographic direction of the Cu(111) surface resulting in a racemic mixture of R-TCT (clockwise) and S-TCT (anticlockwise) enantiomers with respect to the mirror planes perpendicular to the surface. (d) Schematic representation with half arrows of the R-TCT and S-TCT molecules. (e) Chiral geometry of TCT molecules adsorbed along the 3-fold symmetry axes of the surface with an R′ (clockwise) favorable and an S′ (anticlockwise) unfavorable configuration.

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    Figure 3. Thermally induced desulfurization reaction of TCT under the catalytic activity of Cu(111). (a) STM images acquired with a functionalized tip of the TCT and TC-D molecules following adsorption at a temperature of about 300 K. Half arrows mark each molecular isomer. (b, c) Zoom-in images (marked with rectangles in panel (a) together with the STM simulations in the Tersoff–Hamann approximation of the molecular aspect (38) and of the calculated molecular structure of the TCT and TC-D molecules. (d) Arrhenius plot of the TCT desulfurization reaction.

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    Figure 4. STM images of the racemic mixture of TCT and TC-D molecules. (a) Topographic overview image acquired with a functionalized tip. Yellow half arrows are used to mark the TC-D enantiomers. (b) Zoom-in images of TC-D dimers showing different occurrences, with an unfavorable S′ configuration (red marks) of a TC-D molecule in the left panel.

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    This article references 49 other publications.

    1. 1
      Sacchi, M.; Singh, P.; Chisnall, D. M.; Ward, D. J.; Jardine, A. P.; Allison, W.; Ellis, J.; Hedgeland, H. The Dynamics of Benzene on Cu(111): A Combined Helium Spin Echo and Dispersion-Corrected DFT Study into the Diffusion of Physisorbed Aromatics on Metal Surfaces. Faraday Discuss. 2017, 204, 471– 485,  DOI: 10.1039/C7FD00095B
      [Crossref], [PubMed], [CAS], Google Scholar
      1
      The dynamics of benzene on Cu(111): a combined helium spin echo and dispersion-corrected DFT study into the diffusion of physisorbed aromatics on metal surfaces
      Sacchi, M.; Singh, P.; Chisnall, D. M.; Ward, D. J.; Jardine, A. P.; Allison, W.; Ellis, J.; Hedgeland, H.
      Faraday Discussions (2017), 204 (Complex Molecular Surfaces and Interfaces), 471-485CODEN: FDISE6; ISSN:1359-6640. (Royal Society of Chemistry)
      We use helium spin-echo spectroscopy (HeSE) to investigate the dynamics of the diffusion of benzene adsorbed on Cu(111). The results of these measurements show that benzene moves on the surface through an activated jump-diffusion process between the adsorption sites on a Bravais lattice. D. Functional Theory (DFT) calcns. with van der Waals (vdW) corrections help us understand that the mol. diffuses by jumping through non-degenerate hollow sites. The results of the calcns. shed light on the nature of the binding interaction between this prototypical arom. mol. and the metallic surface. The highly accurate HeSE exptl. data provide a quant. stringent benchmark for the vdW correction schemes applied to the DFT calcns. and we compare the performances of several dispersion interaction schemes.
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    2. 2
      Cirera, B.; Riss, A.; Mutombo, P.; Urgel, J. I.; Santos, J.; Di Giovannantonio, M.; Widmer, R.; Stolz, S.; Sun, Q.; Bommert, M.; Fasel, R.; Jelínek, P.; Auwärter, W.; Martín, N.; Écija, D. On-Surface Synthesis of Organocopper Metallacycles through Activation of Inner Diacetylene Moieties. Chem. Sci. 2021, 12, 12806– 12811,  DOI: 10.1039/D1SC03703J
      [Crossref], [PubMed], [CAS], Google Scholar
      2
      On-surface synthesis of organocopper metallacycles through activation of inner diacetylene moieties
      Cirera Borja; Urgel Jose I; Santos Jose; Martin Nazario; Ecija David; Riss Alexander; Auwarter Willi; Mutombo Pingo; Jelinek Pavel; Urgel Jose I; Di Giovannantonio Marco; Widmer Roland; Stolz Samuel; Sun Qiang; Bommert Max; Fasel Roman; Santos Jose; Martin Nazario; Di Giovannantonio Marco; Stolz Samuel; Fasel Roman
      Chemical science (2021), 12 (38), 12806-12811 ISSN:2041-6520.
      The design of organometallic complexes is at the heart of modern organic chemistry and catalysis. Recently, on-surface synthesis has emerged as a disruptive paradigm to design previously precluded compounds and nanomaterials. Despite these advances, the field of organometallic chemistry on surfaces is still at its infancy. Here, we introduce a protocol to activate the inner diacetylene moieties of a molecular precursor by copper surface adatoms affording the formation of unprecedented organocopper metallacycles on Cu(111). The chemical structure of the resulting complexes is characterized by scanning probe microscopy and X-ray photoelectron spectroscopy, being complemented by density functional theory calculations and scanning probe microscopy simulations. Our results pave avenues to the engineering of organometallic compounds and steer the development of polyyne chemistry on surfaces.
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    3. 3
      Heim, D.; Seufert, K.; Auwärter, W.; Aurisicchio, C.; Fabbro, C.; Bonifazi, D.; Barth, J. V. Surface-Assisted Assembly of Discrete Porphyrin-Based Cyclic Supramolecules. Nano Lett. 2010, 10, 122– 128,  DOI: 10.1021/nl9029994
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      3
      Surface-Assisted Assembly of Discrete Porphyrin-Based Cyclic Supramolecules
      Heim, Daniel; Seufert, Knud; Auwaerter, Willi; Aurisicchio, Claudia; Fabbro, Chiara; Bonifazi, Davide; Barth, Johannes V.
      Nano Letters (2010), 10 (1), 122-128CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
      The authors employed de novo synthesized porphyrin modules to construct discrete cyclic supramol. architectures supported on a copper surface. The programmed geometry and functionality of the mol. modules together with their conformational flexibility and substrate interaction yields sym. discrete assemblies, including dimers and chains as well as three- to six-membered cyclic structures. The area of the mol. cavities is extended by creating bicomponent structures combining building blocks with different symmetry.
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    4. 4
      Kaposi, T.; Joshi, S.; Hoh, T.; Wiengarten, A.; Seufert, K.; Paszkiewicz, M.; Klappenberger, F.; Ecija, D.; D̵ord̵ević, L.; Marangoni, T.; Bonifazi, D.; Barth, J. V.; Auwärter, W. Supramolecular Spangling, Crocheting, and Knitting of Functionalized Pyrene Molecules on a Silver Surface. ACS Nano 2016, 10, 7665– 7674,  DOI: 10.1021/acsnano.6b02989
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      4
      Supramolecular Spangling, Crocheting, and Knitting of Functionalized Pyrene Molecules on a Silver Surface
      Kaposi, Tobias; Joshi, Sushobhan; Hoh, Tobias; Wiengarten, Alissa; Seufert, Knud; Paszkiewicz, Matheusz; Klappenberger, Florian; Ecija, David; Djordjevic, Luka; Marangoni, Tomas; Bonifazi, Davide; Barth, Johannes V.; Auwaerter, Willi
      ACS Nano (2016), 10 (8), 7665-7674CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      Pyrenes, as photoactive polycyclic arom. hydrocarbons (PAHs), represent promising modules for the bottom-up assembly of functional nanostructures. Here, we introduce the synthesis of a family of pyrene derivs. peripherally functionalized with pyridin-4-ylethynyl termini and comprehensively characterize their self-assembly abilities on a smooth Ag(111) support by scanning tunneling microscopy. By deliberate selection of no. and geometric positioning of the pyridyl-terminated substituents, two-dimensional arrays, one-dimensional coordination chains, and chiral, porous kagom´e-type networks can be tailored. A comparison to phenyl-functionalized ref. pyrenes, not supporting the self-assembly of ordered structures at low coverage, highlights the role of the pyridyl moieties for supramol. crocheting and knitting. Furthermore, we demonstrate the selective spangling of pores in the two-dimensional pyrene assemblies by a distinct no. of iodine atoms as guests by atomically resolved imaging and complementary XPS.
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    5. 5
      Lawrence, J.; Mohammed, M. S. G.; Rey, D.; Aguilar-Galindo, F.; Berdonces-Layunta, A.; Peña, D.; de Oteyza, D. G. Reassessing Alkyne Coupling Reactions While Studying the Electronic Properties of Diverse Pyrene Linkages at Surfaces. ACS Nano 2021, 15, 4937– 4946,  DOI: 10.1021/acsnano.0c09756
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      5
      Reassessing Alkyne Coupling Reactions While Studying the Electronic Properties of Diverse Pyrene Linkages at Surfaces
      Lawrence, James; Mohammed, Mohammed S. G.; Rey, Dulce; Aguilar-Galindo, Fernando; Berdonces-Layunta, Alejandro; Pena, Diego; de Oteyza, Dimas G.
      ACS Nano (2021), 15 (3), 4937-4946CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      The combination of alkyne and halogen functional groups in the same mol. allows for the possibility of many different reactions when utilized in on-surface synthesis. Here, we use a pyrene-based precursor with both functionalities to examine the preferential reaction pathway when it is heated on an Au(111) surface. Using high-resoln. bond-resolving scanning tunneling microscopy, we identify multiple stable intermediates along the prevailing reaction pathway that initiate with a clearly dominant Glaser coupling, together with a multitude of other side products. Importantly, control expts. with reactants lacking the halogen functionalization reveal the Glaser coupling to be absent and instead show the prevalence of non-dehydrogenative head-to-head alkyne coupling. We perform scanning tunneling spectroscopy on a rich variety of the product structures obtained in these expts., providing key insights into the strong dependence of their HOMO-LUMO gaps on the nature of the intramol. coupling. A clear trend is found of a decreasing gap that is correlated with the conversion of triple bonds to double bonds via hydrogenation and to higher levels of cyclization, particularly with nonbenzenoid product structures. We rationalize each of the studied cases.
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    6. 6
      Smerdon, J. A.; Bode, M.; Guisinger, N. P.; Guest, J. R. Monolayer and Bilayer Pentacene on Cu(111). Phys. Rev. B 2011, 84, 165436,  DOI: 10.1103/PhysRevB.84.165436
      [Crossref], [CAS], Google Scholar
      6
      Monolayer and bilayer pentacene on Cu(111)
      Smerdon, J. A.; Bode, M.; Guisinger, N. P.; Guest, J. R.
      Physical Review B: Condensed Matter and Materials Physics (2011), 84 (16), 165436/1-165436/7CODEN: PRBMDO; ISSN:1098-0121. (American Physical Society)
      The morphol. and electronic structure of pentacene (Pn) deposited on Cu(111) was studied using scanning tunneling microscopy (STM) and spectroscopy (STS). Deposition of a multilayer followed by annealing to reduce coverage to a monolayer results in the formation of either of two unique phases: a two-dimensional herringbone structure previously unobserved for any linear acene to our knowledge, or a "random-tiling" structure. Coverage greater than a monolayer promotes the formation of a bilayer phase similar to that obsd. for Pn/Ag(111). STS shows that the electronic structure of the first layer is strongly modified due to its proximity to the substrate, while the second layer exhibits nearly bulklike electronic structure.
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    7. 7
      Mairena, A.; Zoppi, L.; Seibel, J.; Tröster, A. F.; Grenader, K.; Parschau, M.; Terfort, A.; Ernst, K. H. Heterochiral to Homochiral Transition in Pentahelicene 2D Crystallization Induced by Second-Layer Nucleation. ACS Nano 2017, 11, 865– 871,  DOI: 10.1021/acsnano.6b07424
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      7
      Heterochiral to Homochiral Transition in Pentahelicene 2D Crystallization Induced by Second-Layer Nucleation
      Mairena, Anais; Zoppi, Laura; Seibel, Johannes; Troster, Alix F.; Grenader, Konstantin; Parschau, Manfred; Terfort, Andreas; Ernst, Karl-Heinz
      ACS Nano (2017), 11 (1), 865-871CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      Gaining insight into mol. recognition at the mol. level, in particular, during nucleation of crystallites, is challenging and calls for studying well-defined model systems. Investigated by means of submol. resoln. scanning tunneling microscopy and theor. mol. modeling, we report chiral recognition phenomena in the 2D crystn. of the helical chiral arom. hydrocarbon pentahelicene on a Cu(111) surface. Homochiral, van der Waals bonded dimers constitute building blocks for self-assembly but form heterochiral as well as homochiral long-range-ordered structures. 2D racemate crystals, built up by homochiral dimers of both enantiomers, are obsd. at coverages close to a full monolayer. As soon as the coverage leads to second-layer nucleation, the dense racemate phase in the first layer disappears and a homochiral dimer conglomerate phase of lower 2D d. appears. Our results show that, at the onset of second-layer nucleation, a local change of enantiomeric compn. in the first layer occurs, causing the transition from a 2D racemate to a 2D conglomerate.
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    8. 8
      Schlickum, U.; Decker, R.; Klappenberger, F.; Zoppellaro, G.; Klyatskaya, S.; Auwarter, W.; Neppl, S.; Kern, K.; Brune, H.; Ruben, M.; Barth, J. V. Chiral Kagomé Lattice from Simple Ditopic Molecular Bricks. J. Am. Chem. Soc. 2008, 130, 11778– 11782,  DOI: 10.1021/ja8028119
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      8
      Chiral Kagome Lattice from Simple Ditopic Molecular Bricks
      Schlickum, U.; Decker, R.; Klappenberger, F.; Zoppellaro, G.; Klyatskaya, S.; Auwarter, W.; Neppl, S.; Kern, K.; Brune, H.; Ruben, M.; Barth, J. V.
      Journal of the American Chemical Society (2008), 130 (35), 11778-11782CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      Self-assembly techniques allow for the fabrication of highly organized architectures with at.-level precision. Here, we report on mol.-level scanning tunneling microscopy observations demonstrating the supramol. engineering of complex, regular, and long-range ordered periodic networks on a surface at. lattice using simple linear mol. bricks. The length variation of the employed de novo synthesized linear dicarbonitrile polyphenyl mols. translates to distinct changes of the bonding motifs that lead to hierarchic order phenomena and unexpected changes of the surface tessellations. The achieved 2D org. networks range from a close-packed chevron pattern via a rhombic network to a hitherto unobserved supramol. chiral kagome lattice.
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    9. 9
      Pivetta, M.; Pacchioni, G. E.; Schlickum, U.; Barth, J. V.; Brune, H. Formation of Fe Cluster Superlattice in a Metal-Organic Quantum-Box Network. Phys. Rev. Lett. 2013, 110, 086102,  DOI: 10.1103/PhysRevLett.110.086102
      [Crossref], [PubMed], [CAS], Google Scholar
      9
      Formation of Fe cluster superlattice in a metal-organic quantum-box network
      Pivetta, Marina; Pacchioni, Giulia E.; Schlickum, Uta; Barth, Johannes V.; Brune, Harald
      Physical Review Letters (2013), 110 (8), 086102/1-086102/5CODEN: PRLTAO; ISSN:0031-9007. (American Physical Society)
      The authors report on the self-assembly of Fe adatoms on a Cu(111) surface that is patterned by a metal-org. honeycomb network, formed by coordination of dicarbonitrile pentaphenyl mols. with Cu adatoms. Fe atoms landing on the metal surface are mobile and steered by the quantum confinement of the surface state electrons towards the center of the network hexagonal cavities. In cavities hosting more than one Fe, preferential interat. distances are obsd. The adatoms in each hexagon aggregate into a single cluster upon gentle annealing. These clusters are again centered in the cavities and their size is discerned by their distinct apparent heights.
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    10. 10
      Stradi, D.; Borca, B.; Barja, S.; Garnica, M.; Diaz, C.; Rodriguez-Garcia, J. M.; Alcami, M.; Vázquez de Parga, A. L.; Miranda, R.; Martin, F. Understanding the Self-Assembly of TCNQ on Cu(111): A Combined Study Based on Scanning Tunnelling Microscopy Experiments and Density Functional Theory Simulations. RSC Adv. 2016, 6, 15071– 15079,  DOI: 10.1039/C5RA26320D
      [Crossref], [CAS], Google Scholar
      10
      Understanding the self-assembly of TCNQ on Cu(111): a combined study based on scanning tunnelling microscopy experiments and density functional theory simulations
      Stradi, Daniele; Borca, Bogdana; Barja, Sara; Garnica, Manuela; Diaz, Cristina; Rodriguez-Garcia, Josefa M.; Alcami, Manuel; Vazquez de Parga, Amadeo L.; Miranda, Rodolfo; Martin, Fernando
      RSC Advances (2016), 6 (18), 15071-15079CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
      The structure of self-assembled monolayers of 7,7',8,8'-tetracyano-p-quinodimethane (TCNQ) adsorbed on Cu(111) has been studied using a combination of scanning tunnelling microscopy (STM) expts. and d. functional theory (DFT) calcns. We show that the polymorphism of the self-assembled mol. layer can be controlled by tuning of the exptl. conditions under which the deposition is carried out. When the Cu(111) substrate is held above room temp. (TCu(111) = 350 K) during deposition, a structure is formed in which the two mols. in the unit cell are oriented one perpendicular to the other. Conversely, when the substrate is held at room temp. during deposition and slightly annealed afterwards, a more complex structure with five mols. per unit cell is formed. DFT calcns. complement the exptl. results by revealing that the building blocks of the two superstructures are two mutually orthogonal adsorption configurations of the mol. The relative stability between the two obsd. polymorphs is reproduced by models of the two superstructures based on these two adsorption configurations.
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    11. 11
      Zhong, Q.; Ebeling, D.; Tschakert, J.; Gao, Y.; Bao, D.; Du, S.; Li, C.; Chi, L.; Schirmeisen, A. Symmetry Breakdown of 4,4”-Diamino-p-Terphenyl on a Cu(111) Surface by Lattice Mismatch. Nat. Commun. 2018, 9, 3277,  DOI: 10.1038/s41467-018-05719-y
      [Crossref], [PubMed], [CAS], Google Scholar
      11
      Symmetry breakdown of 4,4"-diamino-p-terphenyl on a Cu(111) surface by lattice mismatch
      Zhong Qigang; Chi Lifeng; Ebeling Daniel; Tschakert Jalmar; Schirmeisen Andre; Gao Yixuan; Bao Deliang; Du Shixuan; Li Chen
      Nature communications (2018), 9 (1), 3277 ISSN:.
      Site-selective functionalization of only one of two identical chemical groups within one molecule is highly challenging, which hinders the production of complex organic macromolecules. Here we demonstrate that adsorption of 4,4"-diamino-p-terphenyl on a metal surface leads to a dissymmetric binding affinity. With low temperature atomic force microscopy, using CO-tip functionalization, we reveal the asymmetric adsorption geometries of 4,4"-diamino-p-terphenyl on Cu(111), while on Au(111) the symmetry is retained. This symmetry breaking on Cu(111) is caused by a lattice mismatch and interactions with the subsurface atomic layer. The dissymmetry results in a change of the binding affinity of one of the amine groups, leading to a non-stationary behavior under the influence of the scanning tip. Finally, we exploit this dissymmetric binding affinity for on-surface self-assembly with 4,4"-diamino-p-terphenyl for side-preferential attachment of 2-triphenylenecarbaldehyde. Our findings provide a new route towards surface-induced dissymmetric activation of a symmetric compound.
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    12. 12
      Morf, P.; Ballav, N.; Putero, M.; von Wrochem, F.; Wessels, J. M.; Jung, T. A. (2010). Supramolecular Structures and Chirality in Dithiocarbamate Self-Assembled Monolayers on Au (111). J. Phys. Chem. Lett. 2010, 1, 813– 816,  DOI: 10.1021/jz900435w
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      12
      Supramolecular Structures and Chirality in Dithiocarbamate Self-Assembled Monolayers on Au(111)
      Morf, Peter; Ballav, Nirmalya; Putero, Magali; von Wrochem, Florian; Wessels, Jurina M.; Jung, Thomas A.
      Journal of Physical Chemistry Letters (2010), 1 (5), 813-816CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
      We report the observation of supramol. structures in a self-assembled monolayer (SAM) of diethyldithiocarbamate (DEDTC) on the Au(111) substrate. While all sulfur atoms are found to be covalently anchored to the gold substrate for both DEDTC and DT (decanethiol) monolayers, the self-assembly behavior of DEDTC has been obsd. to be distinctively different from that of DT. We have found hexagonally arranged trimeric domains of DEDTC mols. in two 30° rotated domains, which we assign to a pattern of chiral trimeric domains. The trimers belong to the C3 point group, and the supramol. assembly shows a (2√3 × 2√3)R15° surface structure.
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    13. 13
      Li, D.; Ding, Y.; Wang, X.; Xu, W. On-Surface Fabrication of Bimetallic Metal–Organic Frameworks through the Synergy and Competition among Noncovalent Interactions. J. Phys. Chem. Lett. 2021, 12, 5228– 5232,  DOI: 10.1021/acs.jpclett.1c00942
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      13
      On-surface fabrication of bimetallic metal-organic frameworks through synergy and competition among noncovalent interactions
      Li, Donglin; Ding, Yuanqi; Wang, Xinyi; Xu, Wei
      Journal of Physical Chemistry Letters (2021), 12 (22), 5228-5232CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
      Two-dimensional metal-org. frameworks (2D-MOFs) are attracting more attention due to their unique properties. Various 2D-MOF structures have been fabricated on surfaces in which either only one kind of metal was incorporated or only one kind of noncovalent interaction was involved in a bimetallic network. However, 2D-MOFs involving different kinds of noncovalent interactions and multiple metal components are more complex and less predictable. Here, we choose the uracil (U) mol. together with alkali metals [sodium (Na) and cesium (Cs)] and a transition metal [iron (Fe)] as model systems and successfully construct two kinds of bimetallic 2D-MOFs through the synergy and competition among noncovalent interactions, which is revealed by the high-resoln. scanning tunneling microscopy imaging and d. functional theory calcns. Such a systematic study may help to improve our fundamental understanding of the interaction mechanism of noncovalent bonds and, moreover, lead to further investigations of the unprecedented functions of surface-supported 2D-MOF structures.
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    14. 14
      Cirera, B.; Giménez-Agulló, N.; Björk, J.; Martínez-Peña, F.; Martin-Jimenez, A.; Rodriguez-Fernandez, J.; Pizarro, A. M.; Otero, R.; Gallego, J. M.; Ballester, P.; Galan-Mascaros, J. R.; Ecija, D. Thermal Selectivity of Intermolecular Versus Intramolecular Reactions on Surfaces. Nat. Commun. 2016, 7, 11002,  DOI: 10.1038/ncomms11002
      [Crossref], [PubMed], [CAS], Google Scholar
      14
      Thermal selectivity of intermolecular versus intramolecular reactions on surfaces
      Cirera, Borja; Gimenez-Agullo, Nelson; Bjork, Jonas; Martinez-Pena, Francisco; Martin-Jimenez, Alberto; Rodriguez-Fernandez, Jonathan; Pizarro, Ana M.; Otero, Roberto; Gallego, Jose M.; Ballester, Pablo; Galan-Mascaros, Jose R.; Ecija, David
      Nature Communications (2016), 7 (), 11002CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
      On-surface synthesis is a promising strategy for engineering heteroat. covalent nanoarchitectures with prospects in electronics, optoelectronics and photovoltaics. Here we report the thermal tunability of reaction pathways of a mol. precursor in order to select intramol. vs. intermol. reactions, yielding monomeric or polymeric phthalocyanine derivs., resp. Deposition of tetra-aza-porphyrin species bearing Et termini on Au(111) held at room temp. results in a close-packed assembly. Upon annealing from room temp. to 275 °C, the mol. precursors undergo a series of covalent reactions via their Et termini, giving rise to phthalocyanine tapes. However, deposition of the tetra-aza-porphyrin derivs. on Au(111) held at 300 °C results in the formation and self-assembly of monomeric phthalocyanines. A systematic scanning tunnelling microscopy study of reaction intermediates, combined with d. functional calcns., suggests a [2+2] cycloaddn. as responsible for the initial linkage between mol. precursors, whereas the monomeric reaction is rationalized as an electrocyclic ring closure.
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    15. 15
      Zint, S.; Ebeling, D.; Ahles, S.; Wegner, H. A.; Schirmeisen, A. Subsurface-Controlled Angular Rotation: Triphenylene Molecules on Au(111) Substrates. J. Phys. Chem. C 2016, 120, 1615– 1622,  DOI: 10.1021/acs.jpcc.5b10602
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      15
      Subsurface-Controlled Angular Rotation: Triphenylene Molecules on Au(111) Substrates
      Zint, Soeren; Ebeling, Daniel; Ahles, Sebastian; Wegner, Hermann A.; Schirmeisen, Andre
      Journal of Physical Chemistry C (2016), 120 (3), 1615-1622CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
      Self-assembly of triphenylene mols. on a reconstructed Au(111) substrate in the submonolayer regime has been studied by scanning tunneling microscopy. Only two different orientations of the planar adsorbed mols. are obsd. At intermediate coverages self-assembly is mainly detd. by repulsive mol.-mol. interactions, leading to a one-to-one ratio of mol. orientations. At 1.0 monolayer coverage, however, a reorientation into close-packed domains occurs, which significantly shifts the ratio of mol. orientations. It is found that this reorientation is controlled by mol.-subsurface interactions, opening new avenues in assembling mols. on surfaces.
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    16. 16
      Kühnle, A.; Linderoth, T. R.; Besenbacher, F. Self-assembly of Monodispersed, Chiral Nanoclusters of Cysteine on the Au (110)-(1× 2) Surface. J. Am. Chem. Soc. 2003, 125, 14680– 14681,  DOI: 10.1021/ja0377403
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      16
      Self-Assembly of Monodispersed, Chiral Nanoclusters of Cysteine on the Au(110)-(1 × 2) Surface
      Kuehnle, Angelika; Linderoth, Trolle R.; Besenbacher, Flemming
      Journal of the American Chemical Society (2003), 125 (48), 14680-14681CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      The self-assembly of monodispersed supramol. nanoclusters was obsd. by scanning tunneling microscopy (STM). The clusters form from the naturally occurring amino acid cysteine by vapor deposition onto the Au(110)-(1 × 2) surface under ultrahigh vacuum conditions. Enantiomerically pure L- and D-cysteine yields clusters with mirror-image STM signatures. Racemic LD-cysteine segregates into homochiral clusters, evidencing specific intermol. interactions during the self-assembly process.
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    17. 17
      Bombis, C.; Weigelt, S.; Knudsen, M. M.; Nørgaard, M.; Busse, C.; Lægsgaard, E.; Besenbacher, F.; Gothelf, K. V.; Linderoth, T. R. Steering Organizational and Conformational Surface Chirality by Controlling Molecular Chemical Functionality. ACS Nano 2010, 4, 297– 311,  DOI: 10.1021/nn9012803
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      17
      Steering Organizational and Conformational Surface Chirality by Controlling Molecular Chemical Functionality
      Bombis, Christian; Weigelt, Sigrid; Knudsen, Martin M.; Noergaard, Martin; Busse, Carsten; Laegsgaard, Erik; Besenbacher, Flemming; Gothelf, Kurt V.; Linderoth, Trolle R.
      ACS Nano (2010), 4 (1), 297-311CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      Mol. chirality on surfaces was widely explored, both for intrinsically chiral mols. and for prochiral mols. that become chiral upon adsorption due to the reduced symmetry which follows from surface confinement. However, little attention was devoted to chiral effects that originate from conformational degrees of freedom for adsorbed mols. Scanning tunneling microscopy was here used to study the self-assembled structures formed when a class of six linear, org. mols. (oligo-phenylene-ethynylenes) are adsorbed on a Au(111) surface under ultrahigh vacuum conditions. All of the studied compds. are intrinsically achiral, but most display conformational chirality in the sense that the mols. can adsorb on the surface in different conformations giving rise to either one of two chiral surface enantiomers or a mirror-sym. achiral meso form. A total of eleven obsd. adsorption structures are systematically studied with respect to conformational chirality as well as point chirality (arising where mol. adsorption locally breaks the substrate symmetry) and organizational chirality (arising from the tiling pattern of the mol. backbones). A no. of interesting correlations are identified between these different levels of chirality. Most importantly, it is possible through control of the terminal group functionalization to steer the oligo(phenylene-ethynylene) mol. backbones into surface assemblies that either display pronounced organizational chirality or have mirror sym. tiling patterns, and it is also possible to control the conformational surface chirality so the compds. preferentially assume either chiral or achiral surface conformers.
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    18. 18
      Masini, F.; Kalashnyk, N.; Knudsen, M. M.; Cramer, J. R.; Lægsgaard, E.; Besenbacher, F.; Gothelf, K. V.; Linderoth, T. R. Chiral Induction by Seeding Surface Assemblies of Chiral Switches. J. Am. Chem. Soc. 2011, 133, 13910– 13913,  DOI: 10.1021/ja205998c
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      18
      Chiral Induction by Seeding Surface Assemblies of Chiral Switches
      Masini, Federico; Kalashnyk, Nataliya; Knudsen, Martin M.; Cramer, Jacob R.; Laegsgaard, Erik; Besenbacher, Flemming; Gothelf, Kurt V.; Linderoth, Trolle R.
      Journal of the American Chemical Society (2011), 133 (35), 13910-13913CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      It is demonstrated by scanning tunneling microscopy that coadsorption of a mol. chiral switch with a complementary, intrinsically chiral induction seed on the Au(111) surface gives globally homochiral mol. assemblies.
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    19. 19
      Grillo, F.; Mugnaini, V.; Oliveros, M.; Francis, S. M.; Choi, D. J.; Rastei, M. V.; Limot, L.; Cepek, C.; Pedio, M.; Bromley, S. T.; Richardson, N. V.; Bucher, J.-P.; Veciana, J. Chiral Conformation at a Molecular Level of a Propeller-Like Open-Shell Molecule on Au (111). J. Phys. Chem. Lett. 2012, 3, 1559– 1564,  DOI: 10.1021/jz3003926
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      19
      Chiral Conformation at a Molecular Level of a Propeller-Like Open-Shell Molecule on Au(111)
      Grillo, Federico; Mugnaini, Veronica; Oliveros, Malena; Francis, Steve M.; Choi, Deung-Jang; Rastei, Mircea V.; Limot, Laurent; Cepek, Cinzia; Pedio, Maddalena; Bromley, Stefan T.; Richardson, Neville V.; Bucher, Jean-Pierre; Veciana, Jaume
      Journal of Physical Chemistry Letters (2012), 3 (11), 1559-1564CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
      A key stage in engineering mol. functional organizations is represented by controlling the supramol. assembly of single mol. building blocks, tectons, into ordered networks. Here, an open-shell, propeller-like mol. was deposited under UHV conditions on Au(111) and its supramol. organization characterized by scanning tunneling microscopy (STM). Racemic islands were obsd. at room temp., and their chirality was imaged at the mol. level at low temp. Modeling further suggests that the obsd. chirally alternating ordering dominated by intermol. interactions is energetically favored. ESR and UV photoemission spectroscopy evidences suggest that the supramol. networks may preserve the open-shell character of the tecton. These results represent a fundamental step forward toward the engineering of purely org. spintronic devices.
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    20. 20
      Dmitriev, A.; Spillmann, H.; Stepanow, S.; Strunskus, T.; Wöll, C.; Seitsonen, A. P.; Lingenfelder, M.; Lin, N.; Barth, J. V.; Kern, K. Asymmetry Induction by Cooperative Intermolecular Hydrogen Bonds in Surface-Anchored Layers of Achiral Molecules. ChemPhysChem 2006, 7, 2197– 2204,  DOI: 10.1002/cphc.200600110
      [Crossref], [PubMed], [CAS], Google Scholar
      20
      Asymmetry induction by cooperative intermolecular hydrogen bonds in surface-anchored layers of achiral molecules
      Dmitriev, Alexandre; Spillmann, Hannes; Stepanow, Sebastian; Strunskus, Thomas; Woell, Christof; Seitsonen, Ari P.; Lingenfelder, Magali; Lin, Nian; Barth, Johannes V.; Kern, Klaus
      ChemPhysChem (2006), 7 (10), 2197-2204CODEN: CPCHFT; ISSN:1439-4235. (Wiley-VCH Verlag GmbH & Co. KGaA)
      The meso-scale induction of two-dimensional supramol. chirality (formation of 2D org. domains with a single handedness) was achieved by self-assembly of 1,2,4-benzenetricarboxylic (trimellitic) acid on a Cu(100) surface at elevated temps. The combination of spectroscopic [XPS and near-edge X-ray absorption fine structure (NEXAFS)], real-space-probe [scanning tunneling microscopy (STM)], and computational [d. functional theory (DFT)] methods allows a comprehensive characterization of the obtained org. ad-layers, where details of mol. adsorption geometry, ir termol. coupling, and surface chem. bonding are elucidated. The trimellitic acid species, comprising three functional carboxylic groups, form distinct stable mirror-sym. hydrogen-bonded domains. The chiral ordering is assocd. with conformational restriction in the domains: mols. anchor to the substrate with an ortho carboxylate group, providing two para carboxylic acid moieties for collective lateral interweaving through H bonding, which induces a specific tilt of the mol. plane. The ease of mol. symmetry switching in domain formation makes homochiral-signature propagation solely limited by the terrace width. The mol. layer modifies the morphol. of the underlying copper substrate and induces μm-sized strictly homochiral terraces.
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    21. 21
      Borca, B.; Schendel, V.; Pétuya, R.; Pentegov, I.; Michnowicz, T.; Kraft, U.; Klauk, H.; Arnau, A.; Wahl, P.; Schlickum, U.; Kern, K. Bipolar Conductance Switching of Single Anthradithiophene Molecules. ACS Nano 2015, 9, 12506– 12512,  DOI: 10.1021/acsnano.5b06000
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      21
      Bipolar Conductance Switching of Single Anthradithiophene Molecules
      Borca, Bogdana; Schendel, Verena; Petuya, Remi; Pentegov, Ivan; Michnowicz, Tomasz; Kraft, Ulrike; Klauk, Hagen; Arnau, Andres; Wahl, Peter; Schlickum, Uta; Kern, Klaus
      ACS Nano (2015), 9 (12), 12506-12512CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      Single mol. switches are basic device elements in org. electronics. The pentacene analog anthradithiophene (ADT) shows a fully reversible binary switching between different adsorption conformations on a metallic surface accompanied by a charge transfer. These transitions are activated locally in single mols. in a low-temp. scanning tunneling microscope. The switching induces changes between bistable orbital structures and energy level alignment at the interface. The most stable geometry, the off state, which all mols. adopt upon evapn., corresponds to a short adsorption distance at which the electronic interactions of the acene rings bend the central part of the mol. toward the surface accompanied by a significant charge transfer from the metallic surface to the ADT mols. This leads to a shift of the LUMO down to the Fermi level (EF). In the on state the mol. has a flat geometry at a larger distance from the surface; consequently the interaction is weaker, resulting in a negligible charge transfer with an orbital structure resembling the HOMO when imaged close to EF. The potential barrier between these two states can be overcome reversibly by injecting charge carriers locally into individual mols. Voltage-controlled current traces show a hysteresis characteristic of a bipolar switching behavior. The interpretation is supported by 1st-principles calcns.
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    22. 22
      Liu, W.; Schuler, B.; Xu, Y.; Moll, N.; Meyer, G.; Gross, L.; Tkatchenko, A. Identical Binding Energies and Work Functions for Distinct Adsorption Structures: Olympicenes on the Cu(111) Surface. J. Phys. Chem. Lett. 2016, 7, 1022– 1027,  DOI: 10.1021/acs.jpclett.6b00223
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      22
      Identical Binding Energies and Work Functions for Distinct Adsorption Structures: Olympicenes on the Cu(111) Surface
      Liu, Wei; Schuler, Bruno; Xu, Yong; Moll, Nikolaj; Meyer, Gerhard; Gross, Leo; Tkatchenko, Alexandre
      Journal of Physical Chemistry Letters (2016), 7 (6), 1022-1027CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
      Ab initio calcns. with van der Waals interactions are used in combination with at. force microscopy expts. to explore the interaction mechanism for three structurally related olympicene mols. adsorbed on the Cu(111) surface. The substitution of a single atom in the olympicene mol. switches the nature of adsorption from predominantly physisorptive character [olympicene on Cu(111)], to an intermediate state [olympicene-derived ketone on Cu(111)], then to chemisorptive character [olympicene radical on Cu(111)]. Despite the remarkable difference in adsorption structures (by up to 0.9 Å in adsorption height) and different nature of bonding, the olympicene, its ketone, and its radical derivs. have essentially identical binding energies and work functions upon interaction with the metal substrate. These findings suggest that the stability and work functions of mol. adsorbates could be rendered insensitive to their adsorption structures, which could be a useful property for (opto)electronic applications.
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    23. 23
      Su, G.; Yang, S.; Li, S.; Butch, C. J.; Filimonov, S. N.; Ren, J. C.; Liu, W. Switchable Schottky Contacts: Simultaneously Enhanced Output Current and Reduced Leakage Current. J. Am. Chem. Soc. 2019, 141, 1628– 1635,  DOI: 10.1021/jacs.8b11459
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      23
      Switchable Schottky Contacts: Simultaneously Enhanced Output Current and Reduced Leakage Current
      Su, Guirong; Yang, Sha; Li, Shuang; Butch, Christopher J.; Filimonov, Sergey N.; Ren, Ji-Chang; Liu, Wei
      Journal of the American Chemical Society (2019), 141 (4), 1628-1635CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      Metal-semiconductor contacts are key components of nanoelectronics and at.-scale integrated circuits. In these components Schottky diodes provide a low forward voltage and a very fast switching rate but suffer the drawback of a high reverse leakage current. Improvement of the reverse bias characteristics without degrading performance of the diode at pos. voltages is deemed phys. impossible for conventional silicon-based Schottky diodes. However, in this work we propose that this design challenge can be overcome in the org.-based diodes by utilizing reversible transitions between distinct adsorption states of org. mols. on metal surfaces. Motivated by previous exptl. observations of controllable adsorption conformations of anthradithiophene on Cu(111), herein we use d. functional theory simulations to demonstrate the distinct Schottky barrier heights of the two adsorption states. The higher Schottky barrier of the reverse bias induced by a chemisorbed state results in low leakage current, while the lower barrier of the forward bias induced by a physisorbed state yields a larger output current. The rectifying behaviors are further supported by nonequil. Green's function transport calcns.
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    24. 24
      Paßens, M.; Caciuc, V.; Atodiresei, N.; Feuerbacher, M.; Moors, M.; Dunin-Borkowski, R. E.; Blügel, S.; Waser, R.; Karthäu-ser, S. Interface-Driven Formation of a Two-Dimensional Dodecag-onal Fullerene Quasicrystal. Nat. Commun. 2017, 8, 15367,  DOI: 10.1038/ncomms15367
      [Crossref], [PubMed], [CAS], Google Scholar
      24
      Interface-driven formation of a two-dimensional dodecagonal fullerene quasicrystal
      Passens, M.; Caciuc, V.; Atodiresei, N.; Feuerbacher, M.; Moors, M.; Dunin-Borkowski, R. E.; Bluegel, S.; Waser, R.; Karthaeuser, S.
      Nature Communications (2017), 8 (), 15367CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
      Since their discovery, quasicrystals have attracted continuous research interest due to their unique structural and phys. properties. Recently, it was demonstrated that dodecagonal quasicrystals could be used as bandgap materials in next-generation photonic devices. However, a full understanding of the formation mechanism of quasicrystals is necessary to control their phys. properties. Here we report the formation of a two-dimensional dodecagonal fullerene quasicrystal on a Pt3Ti(111) surface, which can be described in terms of a square-triangle tiling. Employing d. functional theory calcns., we identify the complex adsorption energy landscape of the Pt-terminated Pt3Ti surface that is responsible for the quasicrystal formation. We demonstrate the presence of quasicrystal-specific phason strain, which provides the degree of freedom required to accommodate the quasicryst. structure on the periodic substrate. Our results reveal detailed insight into an interface-driven formation mechanism and open the way to the creation of tailored fullerene quasicrystals with specific phys. properties.
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    25. 25
      Kakudate, T.; Tsukamoto, S.; Kubo, O.; Nakaya, M.; Nakaya-ma, T. Electronic Structures of Quaterthiophene and Septithiophene on Cu (111): Spatial Distribution of Adsorption-Induced States Studied by STM and DFT Calculation. J. Phys. Chem. C 2016, 120, 6681– 6688,  DOI: 10.1021/acs.jpcc.6b00566
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      25
      Electronic Structures of Quaterthiophene and Septithiophene on Cu(111): Spatial Distribution of Adsorption-Induced States Studied by STM and DFT Calculation
      Kakudate, Toshiyuki; Tsukamoto, Shigeru; Kubo, Osamu; Nakaya, Masato; Nakayama, Tomonobu
      Journal of Physical Chemistry C (2016), 120 (12), 6681-6688CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
      Quaterthiophene (4T) and septithiophene (7T) mols. adsorbed on Cu(111) surfaces have been studied by scanning tunneling microscopy and spectroscopy (STM and STS) at room temp. Both oligothiophene mols. formed one-dimensional (1D) chain structures on Cu(111), and each mol. in the 1D structures was obsd. as a row of bright ovals corresponding to thiophene units. Obsd. features of 4T and 7T mols. differed from those expected from the HOMO and LUMO of the free-standing mols., and d.-functional calcns. of a 4T mol. together with a Cu(111) surface reproduce the exptl. STM images as they reflected characteristic spatial distribution of adsorption-induced states. In other words, the adsorption-induced states were spatially protruding out from the mol. and not completely localized in the space between the mol. and the Cu(111) surface.
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    26. 26
      Schiffrin, A.; Capsoni, M.; Farahi, G.; Wang, C.-G.; Krull, C.; Castelli, M.; Roussy, T.; Cochrane, K. A.; Yin, Y.; Medhekar, N. V.; Fuhrer, M.; Shaw, A. Q.; Ji, W.; Burke, S. A. Designing Optoelectronic Properties by On-Surface Synthesis: Formation and Electronic Structure of an Iron–Terpyridine Macromolecular Complex. ACS Nano 2018, 12, 6545– 6553,  DOI: 10.1021/acsnano.8b01026
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      26
      Designing Optoelectronic Properties by On-Surface Synthesis: Formation and Electronic Structure of an Iron-Terpyridine Macromolecular Complex
      Schiffrin, Agustin; Capsoni, Martina; Farahi, Gelareh; Wang, Chen-Guang; Krull, Cornelius; Castelli, Marina; Roussy, Tanya; Cochrane, Katherine A.; Yin, Yuefeng; Medhekar, Nikhil V.; Fuhrer, Michael; Shaw, Adam Q.; Ji, Wei; Burke, Sarah A.
      ACS Nano (2018), 12 (7), 6545-6553CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      Supramol. chem. protocols applied on surfaces offer compelling avenues for at.-scale control over org.-inorg. interface structures. In this approach, adsorbate-surface interactions and two-dimensional confinement can lead to morphologies and properties that differ dramatically from those achieved via conventional synthetic approaches. Here, we describe the bottom-up, on-surface synthesis of one-dimensional coordination nanostructures based on an iron (Fe)-terpyridine (tpy) interaction borrowed from functional metal-org. complexes used in photovoltaic and catalytic applications. Thermally activated diffusion of sequentially deposited ligands and metal atoms and intraligand conformational changes lead to Fe-tpy coordination and formation of these nanochains. We used low-temp. scanning tunneling microscopy and d. functional theory to elucidate the at.-scale morphol. of the system, suggesting a linear tri-Fe linkage between facing, coplanar tpy groups. Scanning tunneling spectroscopy reveals the highest occupied orbitals, with dominant contributions from states located at the Fe node, and ligand states that mostly contribute to the lowest unoccupied orbitals. This electronic structure yields potential for hosting photoinduced metal-to-ligand charge transfer in the visible/near-IR. The formation of this unusual tpy/tri-Fe/tpy coordination motif has not been obsd. for wet chem. synthetic methods and is mediated by the bottom-up on-surface approach used here, offering pathways to engineer the optoelectronic properties and reactivity of metal-org. nanostructures.
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    27. 27
      Gutzler, R.; Garg, M.; Ast, Ch. R.; Kuhnke, K.; Kern, K. Light–Matter Interaction at Atomic Scales. Nat. Rev. Phys. 2021, 3, 441– 453,  DOI: 10.1038/s42254-021-00306-5
      [Crossref], Google Scholar
      There is no corresponding record for this reference.
    28. 28
      Rossel, F.; Pivetta, M.; Schneider, W.-D. Luminescence Experiments on Supported Molecules with the Scanning Tunneling Microscope. Surf. Sci. Rep. 2010, 65, 129– 144,  DOI: 10.1016/j.surfrep.2010.06.001
      [Crossref], [CAS], Google Scholar
      28
      Luminescence experiments on supported molecules with the scanning tunneling microscope
      Rossel, Frederic; Pivetta, Marina; Schneider, Wolf-Dieter
      Surface Science Reports (2010), 65 (5), 129-144CODEN: SSREDI; ISSN:0167-5729. (Elsevier B.V.)
      The present review on light emission stimulated by electrons tunneling inelastically through a junction formed by a sample and a tip of a scanning tunneling microscope (STM) focusses on the most relevant results obtained for a variety of systems, including metal surfaces, single mols. on ultrathin dielec. films, and mols. assembled in thin films or in nanostructures on metal surfaces or on dielec. films. The decisive role of the localized surface plasmon for the enhanced luminescence from supported mols. is highlighted. The progress so far achieved for both exptl. techniques and theor. anal. is addressed. Current trends are discussed and possible future developments are indicated. STM-induced photon emission has come a long way. More than a decade ago, simple photon maps reflected only the emitted light intensity on a local scale. Today this technique has advanced to spectroscopically resolve optical emission from electronic and vibrational mol. modes in single mols., demonstrating the capability of STM-induced light emission for chem. recognition on the single-mol. scale.
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    29. 29
      Kumar, D.; Hellerstedt, J.; Field, B.; Lowe, B.; Yin, Y.; Medhekar, N. V.; Schiffrin, A. Manifestation of Strongly Correlated Electrons in a 2D Kagome Metal–Organic Framework. Adv. Funct. Mater. 2021, 31, 2106474,  DOI: 10.1002/adfm.202106474
      [Crossref], [CAS], Google Scholar
      29
      Manifestation of Strongly Correlated Electrons in a 2D Kagome Metal-Organic Framework
      Kumar, Dhaneesh; Hellerstedt, Jack; Field, Bernard; Lowe, Benjamin; Yin, Yuefeng; Medhekar, Nikhil V.; Schiffrin, Agustin
      Advanced Functional Materials (2021), 31 (48), 2106474CODEN: AFMDC6; ISSN:1616-301X. (Wiley-VCH Verlag GmbH & Co. KGaA)
      2D and layered electronic materials characterized by a kagome lattice, whose valence band structure includes two Dirac bands and one flat band, can host a wide range of tunable topol. and strongly correlated electronic phases. While strong electron correlations have been obsd. in inorg. kagome crystals, they remain elusive in org. systems, which benefit from versatile synthesis protocols via mol. self-assembly and metal-ligand coordination. Here, direct exptl. evidence of local magnetic moments resulting from strong electron-electron Coulomb interactions in a 2D metal-org. framework (MOF) is reported. The latter consists of di-cyano-anthracene (DCA) mols. arranged in a kagome structure via coordination with copper (Cu) atoms on a silver surface [Ag(111)]. Temp.-dependent scanning tunneling spectroscopy reveals magnetic moments spatially confined to DCA and Cu sites of the MOF, and Kondo screened by the Ag(111) conduction electrons. By d. functional theory and mean-field Hubbard modeling, it is shown that these magnetic moments are the direct consequence of strong Coulomb interactions between electrons within the kagome MOF. The findings pave the way for nanoelectronics and spintronics technologies based on controllable correlated electron phases in 2D org. materials.
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    30. 30
      Garnica, M.; Stradi, D.; Calleja, F.; Barja, S.; Díaz, C.; Alcamí, M.; Arnau, A.; Vázquez de Parga, A. L.; Martín, F.; Miranda, R. Probing the Site-Dependent Kondo Response of Nanostructured Graphene with Organic Molecules. Nano Lett. 2014, 14, 4560– 4567,  DOI: 10.1021/nl501584v
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      30
      Probing the Site-Dependent Kondo Response of Nanostructured Graphene with Organic Molecules
      Garnica, Manuela; Stradi, Daniele; Calleja, Fabian; Barja, Sara; Diaz, Cristina; Alcami, Manuel; Arnau, Andres; Vazquez de Parga, Amadeo L.; Martin, Fernando; Miranda, Rodolfo
      Nano Letters (2014), 14 (8), 4560-4567CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
      TCNQ mols. were used as a sensitive probe for the Kondo response of the electron gas of a nanostructured graphene grown on Ru(0001) presenting a moir´e pattern. All adsorbed mols. acquired an extra electron by charge transfer from the substrate, but only those adsorbed in the FCC-Top areas of the moir´e show magnetic moment and Kondo resonance in the STS spectra. DFT calcns. trace this behavior to the existence of a surface resonance in the low areas of the graphene moir´e, whose d. distribution strongly depends on the stacking sequence of the moir´e area and effectively quenches the magnetic moment for HCP-Top sites.
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    31. 31
      Carbone, C.; Gardonio, S.; Moras, P.; Lounis, S.; Heide, M.; Bihlmayer, G.; Atodiresei, N.; Dederichs, P. H.; Blügel, S.; Vlaic, S.; Lehnert, A.; Ouazi, S.; Rusponi, S.; Brune, H.; Honolka, J.; Enders, A.; Kern, K.; Stepanow, S.; Krull, C.; Balashov, T.; Mugarza, A.; Gambardella, P. Self-Assembled Nanometer-Scale Magnetic Networks on Surfaces: Fundamental Interactions and Functional Properties. Adv. Funct. Mater. 2011, 21, 1212– 1228,  DOI: 10.1002/adfm.201001325
      [Crossref], [CAS], Google Scholar
      31
      Self-Assembled Nanometer-Scale Magnetic Networks on Surfaces: Fundamental Interactions and Functional Properties
      Carbone, Carlo; Gardonio, Sandra; Moras, Paolo; Lounis, Samir; Heide, Marcus; Bihlmayer, Gustav; Atodiresei, Nicolae; Dederichs, Peter Heinz; Bluegel, Stefan; Vlaic, Sergio; Lehnert, Anne; Ouazi, Safia; Rusponi, Stefano; Brune, Harald; Honolka, Jan; Enders, Axel; Kern, Klaus; Stepanow, Sebastian; Krull, Cornelius; Balashov, Timofey; Mugarza, Aitor; Gambardella, Pietro
      Advanced Functional Materials (2011), 21 (7), 1212-1228CODEN: AFMDC6; ISSN:1616-301X. (Wiley-VCH Verlag GmbH & Co. KGaA)
      A review. Nanomagnets of controlled size, organized into regular patterns open new perspectives in the fields of nanoelectronics, spintronics, and quantum computation. Self-assembling processes on various types of substrates allow designing fine-structured architectures and tuning of their magnetic properties. Here, starting from a description of fundamental magnetic interactions at the nanoscale, we review recent exptl. approaches to fabricate zero-, one-, and two-dimensional magnetic particle arrays with dimensions reduced to the at. limit and unprecedented areal d. We describe systems composed of individual magnetic atoms, metal-org. networks, metal wires, and bimetallic particles, as well as strategies to control their magnetic moment, anisotropy, and temp.-dependent magnetic behavior. The investigation of self-assembled subnanometer magnetic particles leads to significant progress in the design of fundamental and functional aspects, mutual interactions among the magnetic units, and their coupling with the environment.
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    32. 32
      Xiong, M.; Gao, Z.; Qin, Y. Spillover in Heterogeneous Catalysis: New Insights and Opportunities. ACS Catal. 2021, 11, 3159– 3172,  DOI: 10.1021/acscatal.0c05567
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      32
      Spillover in Heterogeneous Catalysis: New Insights and Opportunities
      Xiong, Mi; Gao, Zhe; Qin, Yong
      ACS Catalysis (2021), 11 (5), 3159-3172CODEN: ACCACS; ISSN:2155-5435. (American Chemical Society)
      A review. Spillover is a well-known phenomenon in heterogeneous catalysis and is involved in many important reactions. The establishment of the spillover concept opened up a new research field for an in-depth understanding of the dynamic behavior of migrated species on a catalyst surface. However, a comprehensive understanding of spillover remains lacking. In recent years, the development of advanced characterization techniques in combination with well-controlled synthesis methodologies has provided us with increasing worthwhile information about spillover. This Review mainly describes recent progress on the characterization and mechanism of hydrogen spillover and how to effectively utilize the spillover effect for enhanced catalytic performance. Addnl., the challenges remaining in this research area are discussed, and possible research directions for the future are proposed.
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    33. 33
      Nørskov, J. K.; Studt, F.; Abild-Pedersen, F.; Bligaard, T. Fundamental Concepts in Heterogeneous Catalysis; John Wiley & Sons, Inc.: Hoboken, NJ, 2014.  DOI: 10.1002/9781118892114 .
      [Crossref], Google Scholar
      There is no corresponding record for this reference.
    34. 34
      Samantaray, M. K.; D’Elia, V.; Pump, E.; Falivene, L.; Harb, M.; Ould Chikh, S.; Cavallo, L.; Basset, J.-M. The Comparison between Single Atom Catalysis and Surface Organometallic Catalysis. Chem. Rev. 2020, 120, 734– 813,  DOI: 10.1021/acs.chemrev.9b00238
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      34
      The Comparison between Single Atom Catalysis and Surface Organometallic Catalysis
      Samantaray, Manoja K.; D'Elia, Valerio; Pump, Eva; Falivene, Laura; Harb, Moussab; Ould Chikh, Samy; Cavallo, Luigi; Basset, Jean-Marie
      Chemical Reviews (Washington, DC, United States) (2020), 120 (2), 734-813CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
      A review. Single atom catalysis (SAC) is a recent discipline of heterogeneous catalysis for which a single atom on a surface is able to carry out various catalytic reactions. A kind of revolution in heterogeneous catalysis by metals for which it was assumed that specific sites or defects of a nanoparticle were necessary to activate substrates in catalytic reactions. In another extreme of the spectrum, surface organometallic chem. (SOMC), and, by extension, surface organometallic catalysis (SOMCat), have demonstrated that single atoms on a surface, but this time with specific ligands, could lead to a more predictive approach in heterogeneous catalysis. The predictive character of SOMCat was just the result of intuitive mechanisms derived from the elementary steps of mol. chem. This review article will compare the aspects of single atom catalysis and surface organometallic catalysis by considering several specific catalytic reactions, some of which exist for both fields, whereas others might see mutual overlap in the future. After a definition of both domains, a detailed approach of the methods, mostly modeling and spectroscopy, will be followed by a detailed anal. of catalytic reactions: hydrogenation, dehydrogenation, hydrogenolysis, oxidative dehydrogenation, alkane and cycloalkane metathesis, methane activation, metathetic oxidn., CO2 activation to cyclic carbonates, imine metathesis, and selective catalytic redn. (SCR) reactions. A prospective resulting from present knowledge is showing the emergence of a new discipline from the overlap between the two areas.
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    35. 35
      Fox, E. B.; Liu, Z.-W.; Liu, Z.-T. Ultraclean Fuels Production and Utilization for the Twenty-First Century: Advances toward Sustainable Transportation Fuels. Energy Fuels 2013, 27, 6335– 6338,  DOI: 10.1021/ef401094t
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      35
      Ultraclean Fuels Production and Utilization for the Twenty-First Century: Advances toward Sustainable Transportation Fuels
      Fox, Elise B.; Liu, Zhong-Wen; Liu, Zhao-Tie
      Energy & Fuels (2013), 27 (11), 6335-6338CODEN: ENFUEM; ISSN:0887-0624. (American Chemical Society)
      A review. Ultraclean fuels prodn. has become increasingly important as a method to help decrease emissions and allow for the introduction of alternative feedstocks for transportation fuels. Established methods, such as Fischer-Tropsch, have seen a resurgence of interest as natural gas prices drop and existing petroleum resources require more intensive cleanup and purifn. to meet stringent environmental stds. This review covers some of the advances in deep desulfurization and synthesis gas conversion into fuels and feedstocks that were presented at the 245th American Chem. Society (ACS) Spring Annual Meeting in New Orleans, LA, in the Division of Energy and Fuels symposium on "Ultraclean Fuels Prodn. and Utilization".
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    36. 36
      Saha, B.; Vedachalam, S.; Dalai, A. K. Review on Recent Advances in Adsorptive Desulfurization. Fuel Process. Technol. 2021, 214, 106685,  DOI: 10.1016/j.fuproc.2020.106685
      [Crossref], [CAS], Google Scholar
      36
      Review on recent advances in adsorptive desulfurization
      Saha, Biswajit; Vedachalam, Sundaramurthy; Dalai, Ajay K.
      Fuel Processing Technology (2021), 214 (), 106685CODEN: FPTEDY; ISSN:0378-3820. (Elsevier Ltd.)
      A review. The challenges of hydrodesulfurization for desulfurizing the refractory sulfur compds. of petroleum fuels are prompting researchers to investigate the different non-conventional desulfurization techniques. Adsorptive desulfurization (ADS) is emerging as a low-cost alternative to ultra-deep hydrodesulfurization. In ADS, sulfur compds. are removed via physicochem. adsorption using a selective adsorbent. This review focuses on the latest development in ADS. Zeolite, metal oxide, metal-org. framework, mesoporous material, and carbon are assessed for desulfurization of the model and real feedstocks. The ADS performance of these materials can be improved by incorporating metals. Recent progress on improving the selectivity, stability, reusability is discussed. Depending on adsorbent surface chem. compn., sulfur mols. are removed through π complexation, acid-base, metal-sulfur, and Van der Waals forces. The effects of process parameters, thermodn., and kinetics of ADS are also discussed. Selectivity is found to be a key challenge in ADS of real feedstocks due to competitive adsorption. The testing of adsorbents with real fuels is crucial for the commercialization of ADS. Developments of robust adsorbent with less expensive metals and ideal regeneration methods are needed to demonstrate the capabilities of ADS com. The search for a low-cost, and efficient ADS adsorbent is ongoing, and currently, its industrial adaptation is extremely limited.
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    37. 37
      Yang, R. T.; Hernández-Maldonado, A. J.; Yang, F. H. Desulfurization of Transportation Fuels with Zeolites Under Ambient Conditions. Science 2003, 301, 79– 81,  DOI: 10.1126/science.1085088
      [Crossref], [PubMed], [CAS], Google Scholar
      37
      Desulfurization of Transportation Fuels with Zeolites Under Ambient Conditions
      Yang, Ralph T.; Hernandez-Maldonado, Arturo J.; Yang, Frances H.
      Science (Washington, DC, United States) (2003), 301 (5629), 79-81CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
      Deep desulfurization of transportation fuels (gasoline, diesel, and jet fuels) is being mandated by U.S. and foreign governments and is also needed for future fuel cell applications. However, it is extremely difficult and costly to achieve with current technol., which requires catalytic reactors operated at high pressure and temp. We show that Cu+ and Ag+ zeolite Y can adsorb sulfur compds. from com. fuels selectively and with high sulfur capacities (by π complexation) at ambient temp. and pressure. Thus, the sulfur content was reduced from 430 to <0.2 ppm by wt. in a com. diesel at a sorbent capacity of 34 cubic centimeters of clean diesel produced per g of sorbent. This sulfur selectivity and capacity are orders of magnitude higher than those obtained by previously known sorbents.
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    38. 38
      Borca, B.; Michnowicz, T.; Pétuya, R.; Pristl, M.; Schendel, V.; Pentegov, I.; Kraft, U.; Klauk, H.; Wahl, P.; Gutzler, R.; Arnau, A.; Schlickum, U.; Kern, K. Electric-Field-Driven Direct Desulfurization. ACS Nano 2017, 11, 4703– 4709,  DOI: 10.1021/acsnano.7b00612
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      38
      Electric-Field-Driven Direct Desulfurization
      Borca, Bogdana; Michnowicz, Tomasz; Petuya, Remi; Pristl, Marcel; Schendel, Verena; Pentegov, Ivan; Kraft, Ulrike; Klauk, Hagen; Wahl, Peter; Gutzler, Rico; Arnau, Andres; Schlickum, Uta; Kern, Klaus
      ACS Nano (2017), 11 (5), 4703-4709CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      The ability to elucidate the elementary steps of a chem. reaction at the at. scale is important for the detailed understanding of the processes involved, which is key to uncover avenues for improved reaction paths. Here, we track the chem. pathway of an irreversible direct desulfurization reaction of tetracenothiophene adsorbed on the Cu(111) closed-packed surface at the submol. level. Using the precise control of the tip position in a scanning tunneling microscope and the elec. field applied across the tunnel junction, the two carbon-sulfur bonds of a thiophene unit are successively cleaved. Comparison of spatially mapped mol. states close to the Fermi level of the metallic substrate acquired at each reaction step with d. functional theory calcns. reveals the two elementary steps of this reaction mechanism. The first reaction step is activated by an elec. field larger than 2 V nm-1, practically in absence of tunneling electrons, opening the thiophene ring and leading to a transient intermediate. Subsequently, at the same threshold elec. field and with simultaneous injection of electrons into the mol., the exergonic detachment of the sulfur atom is triggered. Thus, a stable mol. with a bifurcated end is obtained, which is covalently bound to the metallic surface. The sulfur atom is expelled from the vicinity of the mol.
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    39. 39
      Michnowicz, T.; Borca, B.; Pétuya, R.; Schendel, V.; Pristl, M.; Pentegov, I.; Kraft, U.; Klauk, H.; Wahl, P.; Mutombo, P.; Jelínek, P.; Arnau, A.; Schlickum, U.; Kern, K. Controlling Single Molecule Conductance by a Locally Induced Chemical Reaction on Individual Thiophene Units. Angew. Chem. Int. . Ed. 2020, 59, 6207– 6212,  DOI: 10.1002/anie.201915200
      [Crossref], [CAS], Google Scholar
      39
      Controlling Single Molecule Conductance by a Locally Induced Chemical Reaction on Individual Thiophene Units
      Michnowicz, Tomasz; Borca, Bogdana; Petuya, Remi; Schendel, Verena; Pristl, Marcel; Pentegov, Ivan; Kraft, Ulrike; Klauk, Hagen; Wahl, Peter; Mutombo, Pingo; Jelinek, Pavel; Arnau, Andres; Schlickum, Uta; Kern, Klaus
      Angewandte Chemie, International Edition (2020), 59 (15), 6207-6212CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)
      Among the prerequisites for the progress of single-mol.-based electronic devices are a better understanding of the electronic properties at the individual mol. level and the development of methods to tune the charge transport through mol. junctions. Scanning tunneling microscopy (STM) is an ideal tool not only for the characterization, but also for the manipulation of single atoms and mols. on surfaces. The conductance through a single mol. can be measured by contacting the mol. with at. precision and forming a mol. bridge between the metallic STM tip electrode and the metallic surface electrode. The parameters affecting the conductance are mainly related to their electronic structure and to the coupling to the metallic electrodes. Here, the exptl. and theor. analyses are focused on single tetracenothiophene mols. and demonstrate that an in situ-induced direct desulfurization reaction of the thiophene moiety strongly improves the mol. anchoring by forming covalent bonds between mol. carbon and copper surface atoms. This bond formation leads to an increase of the conductance by about 50 % compared to the initial state.
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    40. 40
      Ohmann, R.; Levita, G.; Vitali, L.; De Vita, A.; Kern, K. Influence of Subsurface Layers on the Adsorption of Large Organic Molecules on Close-Packed Metal Surfaces. ACS Nano 2011, 5, 1360– 1365,  DOI: 10.1021/nn103058e
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      40
      Influence of Subsurface Layers on the Adsorption of Large Organic Molecules on Close-Packed Metal Surfaces
      Ohmann, Robin; Levita, Giacomo; Vitali, Lucia; De Vita, Alessandro; Kern, Klaus
      ACS Nano (2011), 5 (2), 1360-1365CODEN: ANCAC3; ISSN:1936-0851. (American Chemical Society)
      The asym. mol. 4-[trans-2-(pyrid-4-yl-vinyl)] benzoic acid (PVBA) adsorbed on Cu(111) is characterized by scanning tunneling microscopy (STM) and d. functional theory (DFT) to det. the influence of subsurface at. layers on the adsorption. In contrast to the 6-fold symmetry of the 1st at. layer of close-packed surfaces, the arrangement of the isolated mols. follows predominantly a 3-fold symmetry. This redn. in symmetry, where the mol. selects a specific orientation along the -211 axes, reveals the contribution of lower-lying Cu layers to the mol. arrangement. The calcns. rationalize the interaction of the substrate with the mol. in terms of electrostatic screening and local relaxation phenomena.
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    41. 41
      Lagoute, J.; Kanisawa, K.; Fölsch, S. Manipulation and Adsorption-Site Mapping of Single Pentacene Molecules on Cu (111). Phys. Rev. B 2004, 70, 245415,  DOI: 10.1103/PhysRevB.70.245415
      [Crossref], [CAS], Google Scholar
      41
      Manipulation and adsorption-site mapping of single pentacene molecules on Cu(111)
      Lagoute, Jerome; Kanisawa, Kiyoshi; Folsch, Stefan
      Physical Review B: Condensed Matter and Materials Physics (2004), 70 (24), 245415/1-245415/6CODEN: PRBMDO; ISSN:1098-0121. (American Physical Society)
      Low-temp. scanning tunneling microscopy at 7 K is used to study the adsorption and manipulation of single pentacene mols. on Cu(111). Controlled lateral translations of the mol. are performed along different high-symmetry directions of the substrate via attractive tip-mol. interactions. By a detailed site-mapping technique combining lateral manipulations of the mol. and of native substrate adatoms the authors det. the adsorptive configuration of the arom. mol. The authors find a planar adsorption geometry with the long mol. axis aligned with the close-packed Cu atom rows and the benzene units centered over hcp. hollow sites of the substrate.
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    42. 42
      Toyoda, K.; Nakano, Y.; Hamada, I.; Lee, K.; Yanagisawa, S.; Morikawa, Y. 2009. First-Principles Study of the Pentacene/Cu (111) Interface: Adsorption States and Vacuum Level Shifts. J. Electron Spectrosc. 2009, 174, 78– 84,  DOI: 10.1016/j.elspec.2009.04.005
      [Crossref], [CAS], Google Scholar
      42
      First-principles study of the pentacene/Cu(111) interface. Adsorption states and vacuum level shifts
      Toyoda, Kenji; Nakano, Yosuke; Hamada, Ikutaro; Lee, Kyuho; Yanagisawa, Susumu; Morikawa, Yoshitada
      Journal of Electron Spectroscopy and Related Phenomena (2009), 174 (1-3), 78-84CODEN: JESRAW; ISSN:0368-2048. (Elsevier B.V.)
      We have studied the interaction of pentacene with a Cu(1 1 1) surface using d. functional theory (DFT) within a generalized gradient approxn. (GGA) and the van der Waals d. functional. The adsorption energy is accurately predicted by vdW-DF, while the equil. distances between pentacene and the metal substrate (Z C) are overestimated by both GGA and vdW-DF. The work function changes depend significantly on Z C. The exptl. work function change can be successfully reproduced by GGA if the exptl. reported adsorption geometry is used, whereas the magnitude of the work function change is underestimated if calcd. adsorption geometries are applied. We examd. the IDIS model to compare it with the GGA results. The interface dipoles estd. by the IDIS model fairly agree with the GGA results, provided that the adsorption distance is large. On the other hand, they tend to deviate from the GGA results as the adsorption distance becomes smaller, where back donation from the metal surface to the adsorbate occurs. At exptl. reported metal-org. distance, back donation is significant enough to induce polarization of pentacene mols. perpendicular to the surface, which leads to a redn. of the work function. Thus, at the exptl. reported metal-org. distance, the work function change estd. by a simple IDIS model deviates from that calcd. by self-consistent GGA calcns. At the exptl. reported metal-org. distance, the transferred electrons create weak chem. bonds between pentacene and the Cu(1 1 1) surface, illustrating the reactive nature of pentacene.
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    43. 43
      Hu, Z. X.; Lan, H.; Ji, W. Role of the Dispersion Force in Modeling the Interfacial Properties of Molecule-Metal Interfaces: Ad-sorption of Thiophene on Copper Surfaces. Sci. Rep. 2014, 4, 5036,  DOI: 10.1038/srep05036
      [Crossref], [PubMed], [CAS], Google Scholar
      43
      Role of the dispersion force in modeling the interfacial properties of molecule-metal interfaces: adsorption of thiophene on copper surfaces
      Hu, Zhi-Xin; Lan, Haiping; Ji, Wei
      Scientific Reports (2014), 4 (), 5036CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)
      We present d. functional theory calcns. of the geometry, adsorption energy and electronic structure of thiophene adsorbed on Cu(111), Cu(110) and Cu(100) surfaces. Our calcns. employ dispersion corrections and self-consistent van der Waals d. functionals (vdW-DFs). In terms of speed and accuracy, we find that the dispersion-energy-cor. Revised Perdue-Burke-Enzerhof (RPBE) functional is the "best balanced" method for predicting structural and energetic properties, while vdW-DF is also highly accurate if a proper exchange functional is used. Discrepancies between theory and expt. in mol. geometry can be solved by considering x-ray generated core-holes. However, the discrepancy concerning the adsorption site for thiophene/Cu(100) remains unresolved and requires both further expts. and deeper theor. anal. For all the interfaces, the PBE functional reveals a covalent bonding picture which the inclusion of dispersive contributions does not change to a vdW one. Our results provide a comprehensive understanding of the role of dispersive forces in modeling mol.-metal interfaces.
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    44. 44
      Lechner, B. A.; Sacchi, M.; Jardine, A. P.; Hedgeland, H.; Allison, W.; Ellis, J.; Jenkins, S. J.; Dastoor, P. C.; Hinch, B. J. (2013). Jumping, Rotating, and Flapping: The Atomic-Scale Motion of Thiophene on Cu (111). J. Phys. Chem. Lett. 2013, 4, 1953– 1958,  DOI: 10.1021/jz400639c
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      44
      Jumping, Rotating, and Flapping: The Atomic-Scale Motion of Thiophene on Cu(111)
      Lechner, Barbara A. J.; Sacchi, Marco; Jardine, Andrew P.; Hedgeland, Holly; Allison, William; Ellis, John; Jenkins, Stephen J.; Dastoor, Paul C.; Hinch, B. J.
      Journal of Physical Chemistry Letters (2013), 4 (11), 1953-1958CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
      The authors investigated the dynamics of isolated thiophene mols. on Cu(111) by combining helium spin-echo (HeSE) spectroscopy with d. functional theory calcns. The thiophene/Cu(111) system displays a rich array of aperiodic dynamical phenomena that include jump diffusion between adjacent atop sites over a 59-62 meV barrier and activated rotation around a sulfur-copper anchor, two processes that have been obsd. previously for related systems. In addn., the authors present exptl. evidence for a new, weakly activated process, the flapping of the mol. ring. Repulsive inter-adsorbate interactions and an exceptionally high friction coeff. of 5 ± 2 ps-1 were also obsd. These expts. demonstrate the versatility of the HeSE technique, and the quant. information extd. in a detailed anal. provides an ideal benchmark for state-of-the-art theor. techniques including nonlocal adsorbate-substrate interactions.
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    45. 45
      Kraft, U.; Anthony, J. E.; Ripaud, E.; Loth, M. A.; Weber, E.; Klauk, H. Low-Voltage Organic Transistors Based on Tetraceno[2,3-b]thiophene: Contact Resistance and Air Stability. Chem. Mater. 2015, 27, 998– 1004,  DOI: 10.1021/cm5043183
      [ACS Full Text ACS Full Text], [CAS], Google Scholar
      45
      Low-Voltage Organic Transistors Based on Tetraceno[2,3-b]thiophene: Contact Resistance and Air Stability
      Kraft, Ulrike; Anthony, John E.; Ripaud, Emilie; Loth, Marsha A.; Weber, Edwin; Klauk, Hagen
      Chemistry of Materials (2015), 27 (3), 998-1004CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
      The small-mol. org. semiconductor tetraceno[2,3-b]thiophene was synthesized through an environmentally friendly synthetic route, using NaBH4, rather than Al/HgCl2, for the redn. of the quinone. Low-voltage org. thin-film transistors (TFTs) were fabricated using tetraceno[2,3-b]thiophene and, for comparison, pentacene and anthradithiophene as the semiconductor. The tetraceno[2,3-b]thiophene TFTs have an effective field-effect mobility as large as 0.55 cm2 V-1 s-1 and a subthreshold swing of 0.13 V/decade. The contact resistance of the tetraceno[2,3-b]thiophene TFTs is substantially smaller than that of the anthradithiophene TFTs and similar to that of the pentacene TFTs. The long-term air stability of TFTs based on all three semiconductors was monitored over a period of 12 mo. The initial charge-carrier mobility of the tetraceno[2,3-b]thiophene TFTs is ∼50% smaller than that of the pentacene TFTs, but as a result of the greater ionization potential and better air stability induced by the terminal thiophene ring condensed at the thiophene-b-bond, the tetraceno[2,3-b]thiophene TFTs outperform the pentacene TFTs after continuous exposure to ambient air for just 3 mo.
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      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXks1Omuw%253D%253D&md5=2bd8d8f46fec9cb12176dc47d35917df
    46. 46
      Horcas, I.; Fernández, R.; Gómez-Rodríguez, J. M.; Colchero, J.; Gómez-Herrero, J.; Baró, A. M. WSXM: A Software for Scanning Probe Microscopy and a Tool for Nanotechnology. Rev. Sci. Instrum. 2007, 78, 013705,  DOI: 10.1063/1.2432410
      [Crossref], [PubMed], [CAS], Google Scholar
      46
      WSXM: a software for scanning probe microscopy and a tool for nanotechnology
      Horcas, I.; Fernandez, R.; Gomez-Rodriguez, J. M.; Colchero, J.; Gomez-Herrero, J.; Baro, A. M.
      Review of Scientific Instruments (2007), 78 (1), 013705/1-013705/8CODEN: RSINAK; ISSN:0034-6748. (American Institute of Physics)
      In this work we briefly describe the most relevant features of WSXM, a freeware scanning probe microscopy software based on MS-Windows. The article is structured in three different sections: The introduction is a perspective on the importance of software on scanning probe microscopy. The second section is devoted to describe the general structure of the application; in this section the capabilities of WSXM to read third party files are stressed. Finally, a detailed discussion of some relevant procedures of the software is carried out.
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    47. 47
      Berland, K.; Hyldgaard, P. Exchange Functional that Test the Robustness of the Plasmon Description of the van der Waals Density Functional. Phys. Rev. B 2014, 89, 035412,  DOI: 10.1103/PhysRevB.89.035412
      [Crossref], [CAS], Google Scholar
      47
      Exchange functional that tests the robustness of the plasmon description of the van der Waals density functional
      Berland, Kristian; Hyldgaard, Per
      Physical Review B: Condensed Matter and Materials Physics (2014), 89 (3), 035412/1-035412/8CODEN: PRBMDO; ISSN:1098-0121. (American Physical Society)
      Is the plasmon description within the nonlocal correlation of the van der Waals d. functional by Dion and coworkers (vdW-DF) robust enough to describe all exchange-correlation components. To address this question, we design an exchange functional based on this plasmon description as well as recent anal. on exchange in the large-s regime. In the regime with reduced gradients s = |.del.n|/2nkF(n) smaller than ≈2.5, dominating the nonlocal correlation part of the binding energy, the enhancement factor Fx(s) closely resembles the Langreth-Vosko screened exchange. In the s regime beyond, dominated by exchange, Fx(s) passes smoothly over to the revised Perdew-Wang-86 form. We term the specific exchange functional LV-PW86r, whereas the full van der Waals functional version emphasizing consistent handling of exchange is termed vdW-DF-cx. Our tests indicate that vdW-DF-cx produces accurate sepns. and binding energies of the S22 data set of mol. dimers as well as accurate lattice consts. and bulk moduli of layered materials and tightly bound solids. These results suggest that the plasmon description within vdW-DF gives a good description of both exchange and correlation effects in the low-to-moderae s regime.
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      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXktlOjt70%253D&md5=f6e4df9fcf3eeea885d81a61f3244647
    48. 48
      Kresse, G.; Furthmüller, J. Efficiency of Ab-Initio Total Energy Calculations for Metals and Semiconductors using a Plane-Wave Basis Set. Comput. Mater. Sci. 1996, 6, 15,  DOI: 10.1016/0927-0256(96)00008-0
      [Crossref], [CAS], Google Scholar
      48
      Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
      Kresse, G.; Furthmuller, J.
      Computational Materials Science (1996), 6 (1), 15-50CODEN: CMMSEM; ISSN:0927-0256. (Elsevier)
      The authors present a detailed description and comparison of algorithms for performing ab-initio quantum-mech. calcns. using pseudopotentials and a plane-wave basis set. The authors will discuss: (a) partial occupancies within the framework of the linear tetrahedron method and the finite temp. d.-functional theory, (b) iterative methods for the diagonalization of the Kohn-Sham Hamiltonian and a discussion of an efficient iterative method based on the ideas of Pulay's residual minimization, which is close to an order N2atoms scaling even for relatively large systems, (c) efficient Broyden-like and Pulay-like mixing methods for the charge d. including a new special preconditioning optimized for a plane-wave basis set, (d) conjugate gradient methods for minimizing the electronic free energy with respect to all degrees of freedom simultaneously. The authors have implemented these algorithms within a powerful package called VAMP (Vienna ab-initio mol.-dynamics package). The program and the techniques have been used successfully for a large no. of different systems (liq. and amorphous semiconductors, liq. simple and transition metals, metallic and semi-conducting surfaces, phonons in simple metals, transition metals and semiconductors) and turned out to be very reliable.
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    49. 49
      Momma, K.; Izumi, F. VESTA: A Three-Dimensional Visualization System for Electronic and Structural Analysis. J. Appl. Crystallogr. 2008, 41, 653– 658,  DOI: 10.1107/S0021889808012016
      [Crossref], [CAS], Google Scholar
      49
      VESTA: a three-dimensional visualization system for electronic and structural analysis
      Momma, Koichi; Izumi, Fujio
      Journal of Applied Crystallography (2008), 41 (3), 653-658CODEN: JACGAR; ISSN:0021-8898. (International Union of Crystallography)
      A cross-platform program, VESTA, has been developed to visualize both structural and volumetric data in multiple windows with tabs. VESTA represents crystal structures by ball-and-stick, space-filling, polyhedral, wire frame, stick, dot-surface and thermal-ellipsoid models. A variety of crystal-chem. information is extractable from fractional coordinates, occupancies and oxidn. states of sites. Volumetric data such as electron and nuclear densities, Patterson functions, and wavefunctions are displayed as isosurfaces, bird's-eye views and two-dimensional maps. Isosurfaces can be colored according to other phys. quantities. Translucent isosurfaces and/or slices can be overlapped with a structural model. Collaboration with external programs enables the user to locate bonds and bond angles in the 'graphics area', simulate powder diffraction patterns, and calc. site potentials and Madelung energies. Electron densities detd. exptl. are convertible into their Laplacians and electronic energy densities.
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    • Experimental results on the desulfurization reaction of TCT molecules by adsorption at a temperature of about 300 K on Cu(111) (PDF)


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