Cart
Article
SM6: A Density Functional Theory Continuum Solvation Model for Calculating Aqueous Solvation Free Energies of Neutrals, Ions, and Solute−Water Clusters
Full Text HTML
Hi-Res PDFPurchase the full-text
- PDF/HTML,
figures/images,
references and tables,
(where available)
Abstract
A new charge model, called Charge Model 4 (CM4), and a new continuum solvent model, called Solvation Model 6 (SM6), are presented. Using a database of aqueous solvation free energies for 273 neutrals, 112 ions, and 31 ion−water clusters, parameter sets for the mPW0 hybrid density functional of Adamo and Barone (Adamo, C.; Barone, V. J. Chem. Phys. 1998, 108, 664−675) were optimized for use with the following four basis sets: MIDI!6D, 6-31G(d), 6-31+G(d), and 6-31+G(d,p). SM6 separates the observable aqueous solvation free energy into two different components: one arising from long-range bulk electrostatic effects and a second from short-range interactions between the solute and solvent molecules in the first solvation shell. This partition of the observable solvation free energy allows SM6 to effectively model a wide range of solutes. For the 273 neutral solutes in the test set, SM6 achieves an average error of 
0.50 kcal/mol in the aqueous solvation free energies. For solutes, especially ions, that have highly concentrated regions of charge density, adding an explicit water molecule to the calculation significantly improves the performance of SM6 for predicting solvation free energies. The performance of SM6 was tested against several other continuum models, including SM5.43R and several different implementations of the Polarizable Continuum Model (PCM). For both neutral and ionic solutes, SM6 outperforms all of the models against which it was tested. Also, SM6 is the only model (except for one with an average error 3.4 times larger) that improves when an explicit solvent molecule is added to solutes with concentrated charge densities. Thus, in SM6, unlike the other continuum models tested here, adding one or more explicit solvent molecules to the calculation is an effective strategy for improving the prediction of the aqueous solvation free energies of solutes with strong local solute−solvent interactions. This is important, because local solute−solvent interactions are not specifically accounted for by bulk electrostatics, but modeling these interactions correctly is important for predicting the aqueous solvation free energies of certain solutes. Finally, SM6 retains its accuracy when used in conjunction with the B3LYP and B3PW91 functionals, and in fact the solvation parameters obtained with a given basis set may be used with any good density functional or fraction of Hartree−Fock exchange.
Citing Articles
Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.
This article has been cited by 90 ACS Journal articles (5 most recent appear below).
Charge Model 5: An Extension of Hirshfeld Population Analysis for the Accurate Description of Molecular Interactions in Gaseous and Condensed Phases
Aleksandr V. Marenich, Steven V. Jerome, Christopher J. Cramer, and Donald G. TruhlarJournal of Chemical Theory and Computation2012 Article ASAPCharge Model 5: An Extension of Hirshfeld Population Analysis for the Accurate Description of Molecular Interactions in Gaseous and Condensed Phases
Aleksandr V. Marenich, Steven V. Jerome, Christopher J. Cramer, and Donald G. TruhlarJournal of Chemical Theory and Computation2012 Article ASAPWe propose a novel approach to deriving partial atomic charges from population analysis. The new model, called Charge Model 5 (CM5), yields class IV partial atomic charges by mapping from those obtained by Hirshfeld population analysis of density ...
Aqueous Solvation of Polyalanine α-Helices with Specific Water Molecules and with the CPCM and SM5.2 Aqueous Continuum Models Using Density Functional Theory
Mateusz Marianski and J. J. DannenbergThe Journal of Physical Chemistry B2012 116 (4), 1437-1445Aqueous Solvation of Polyalanine α-Helices with Specific Water Molecules and with the CPCM and SM5.2 Aqueous Continuum Models Using Density Functional Theory
Mateusz Marianski and J. J. DannenbergThe Journal of Physical Chemistry B2012 116 (4), 1437-1445We present density functional theory (DFT) calculations at the X3LYP/D95(d,p) level on the solvation of polyalanine α-helices in water. The study includes the effects of discrete water molecules and the CPCM and AMSOL SM5.2 solvent continuum model both ...
Stability and Structures of Aluminosilicate Clusters
Chao-Shiang Yang, José Miguel Mora-Fonz, and C. Richard A. CatlowThe Journal of Physical Chemistry C2011 115 (49), 24102-24114Stability and Structures of Aluminosilicate Clusters
Chao-Shiang Yang, José Miguel Mora-Fonz, and C. Richard A. CatlowThe Journal of Physical Chemistry C2011 115 (49), 24102-24114We investigate the structures of stabilities of small aluminosilicate clusters using molecular simulations employing density functional theory (DFT) and the conductor like screening model (COSMO), which allow us to model clusters both in the gas phase as ...
Use of Solution-Phase Vibrational Frequencies in Continuum Models for the Free Energy of Solvation
Raphael F. Ribeiro, Aleksandr V. Marenich, Christopher J. Cramer, and Donald G. TruhlarThe Journal of Physical Chemistry B2011 115 (49), 14556-14562Use of Solution-Phase Vibrational Frequencies in Continuum Models for the Free Energy of Solvation
Raphael F. Ribeiro, Aleksandr V. Marenich, Christopher J. Cramer, and Donald G. TruhlarThe Journal of Physical Chemistry B2011 115 (49), 14556-14562We find that vibrational contributions to a solute’s free energy are in general insensitive to whether the solute vibrational frequencies are computed in the gas phase or in solution. In most cases, the difference is smaller than the intrinsic error in ...
Field-Extremum Model for Short-Range Contributions to Hydration Free Energy
Anna Pomogaeva and Daniel M. ChipmanJournal of Chemical Theory and Computation2011 7 (12), 3952-3960Field-Extremum Model for Short-Range Contributions to Hydration Free Energy
Anna Pomogaeva and Daniel M. ChipmanJournal of Chemical Theory and Computation2011 7 (12), 3952-3960The performance in describing hydration free energies of a broad class of neutral, cationic, and anionic solutes is tested for the recently proposed FESR (Field-Extremum Short-Range) implicit solvation model for interactions between the solute and nearby ...
Tools
-
Add to Favorites
-
Download Citation
-
Email a Colleague -
Permalink
Order Reprints
Rights & Permissions
Citation Alerts
History
- Published In Issue November 08, 2005
- Received June 28, 2005
ACS
Network
Facebook
Tweet This
CiteULike
Newsvine
Digg This
Delicious
