Venturing into Unexplored Phase Space: Synthesis, Structure, and Properties of MgCo3B2 Featuring a Rumpled Kagomé NetworkClick to copy article linkArticle link copied!
- Paul OftedahlPaul OftedahlDepartment of Chemistry, Iowa State University, Ames, Iowa 50011, United StatesMore by Paul Oftedahl
- Nawsher J. ParvezNawsher J. ParvezDepartment of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United StatesMore by Nawsher J. Parvez
- Zhen ZhangZhen ZhangDepartment of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United StatesMore by Zhen Zhang
- Yang Sun
- Vladimir AntropovVladimir AntropovDepartment of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United StatesU.S. Department of Energy, Ames National Laboratory, Ames, Iowa 50011, United StatesMore by Vladimir Antropov
- John Q. XiaoJohn Q. XiaoDepartment of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United StatesMore by John Q. Xiao
- Julia V. Zaikina*Julia V. Zaikina*Email: [email protected]Department of Chemistry, Iowa State University, Ames, Iowa 50011, United StatesMore by Julia V. Zaikina
Abstract
MgCo3B2, a novel ternary boride in a previously unexplored phase space, was synthesized using the hydride route. In situ powder X-ray diffraction and DFT calculations aided in the discovery of this compound, whose structure was then determined by single-crystal X-ray diffraction. Like the closely related CeCo3B2, MgCo3B2 crystallizes in centrosymmetric space group P6/mmm (a = 4.883(2) Å, c = 2.926(2) Å at 210 K, Z = 1). Unlike CeCo3B2, however, it adopts a disordered structure that features a rumpled Kagomé network of Co atoms, and Mg atoms fill the channels of a Co–B framework. Although the structural disorder leads to motifs that are similar to those observed in MgNi3B2 and other related ternary borides, no evidence of an ordered superstructure was found by single-crystal X-ray diffraction or high-resolution powder X-ray diffraction. In the case of CeCo3B2, boron atoms occupy the center of regular Co6 trigonal prisms; in MgCo3B2, boron atoms are shifted from the center of the prism to form B–B dimers with roughly the same length as those found in MgNi3B2. Magnetic susceptibility data exhibit an unusual temperature dependence that cannot be convincingly modeled by the modified Curie–Weiss equation, consistent with DFT calculations predicting a nonmagnetic ground state. Intrinsic susceptibility at 300 K is 1.42 × 10–3 emu/mol Oe, which is comparable to that of paramagnetic YCo3B2 and CeCo3B2 with a similar structure and composition. This study showcases the efficacy of combining several methodologies to discover new solids in unexplored phase spaces. This approach includes in situ PXRD data to monitor reactions of precursors upon heating, a diffusion-enhanced synthesis method, and DFT assessment of compound stability.
Cited By
This article has not yet been cited by other publications.
Article Views
Altmetric
Citations
Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.
Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.
The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.