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DOE OSTI · 1687783

Materials Data on VCo4 by Materials Project

Abstract

VCo4 is alpha La-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. V is bonded to six equivalent V and six equivalent Co atoms to form VV6Co6 cuboctahedra that share corners with six equivalent VV6Co6 cuboctahedra, corners with six CoCo12 cuboctahedra, edges with six equivalent VV6Co6 cuboctahedra, edges with eighteen CoCo12 cuboctahedra, faces with six equivalent VV6Co6 cuboctahedra, and faces with twelve equivalent CoV3Co9 cuboctahedra. All V–V bond lengths are 2.52 Å. All V–Co bond lengths are 2.57 Å. There are six inequivalent Co sites. In the first Co site, Co is bonded to three equivalent V and nine Co atoms to form CoV3Co9 cuboctahedra that share corners with twelve CoV3Co9 cuboctahedra, edges with six equivalent VV6Co6 cuboctahedra, edges with eighteen CoV3Co9 cuboctahedra, faces with six equivalent VV6Co6 cuboctahedra, and faces with twelve CoV3Co9 cuboctahedra. There are three shorter (2.49 Å) and six longer (2.52 Å) Co–Co bond lengths. In the second Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with three equivalent VV6Co6 cuboctahedra, corners with nine CoV3Co9 cuboctahedra, edges with three equivalent VV6Co6 cuboctahedra, edges with twenty-one CoV3Co9 cuboctahedra, and faces with eighteen CoV3Co9 cuboctahedra. There are three shorter (2.48 Å) and six longer (2.52 Å) Co–Co bond lengths. In the third Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with three equivalent VV6Co6 cuboctahedra, corners with nine CoV3Co9 cuboctahedra, edges with three equivalent VV6Co6 cuboctahedra, edges with twenty-one CoV3Co9 cuboctahedra, and faces with eighteen CoV3Co9 cuboctahedra. There are three shorter (2.49 Å) and six longer (2.52 Å) Co–Co bond lengths. In the fourth Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with three equivalent VV6Co6 cuboctahedra, corners with nine CoCo12 cuboctahedra, edges with three equivalent VV6Co6 cuboctahedra, edges with twenty-one CoCo12 cuboctahedra, and faces with eighteen CoCo12 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.48–2.52 Å. In the fifth Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with three equivalent VV6Co6 cuboctahedra, corners with nine CoV3Co9 cuboctahedra, edges with three equivalent VV6Co6 cuboctahedra, edges with twenty-one CoV3Co9 cuboctahedra, and faces with eighteen CoV3Co9 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.48–2.52 Å. In the sixth Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with three equivalent VV6Co6 cuboctahedra, corners with nine CoV3Co9 cuboctahedra, edges with three equivalent VV6Co6 cuboctahedra, edges with twenty-one CoV3Co9 cuboctahedra, and faces with eighteen CoV3Co9 cuboctahedra. There are three shorter (2.49 Å) and six longer (2.52 Å) Co–Co bond lengths.

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2020-06-05. Materials Data on VCo4 by Materials Project. https://doi.org/10.17188/1687783

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