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DOE OSTI · 1721063

Materials Data on VSiW by Materials Project

Abstract

VWSi crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent V2+ sites. In the first V2+ site, V2+ is bonded in a hexagonal planar geometry to six Si4- atoms. There are a spread of V–Si bond distances ranging from 2.38–2.43 Å. In the second V2+ site, V2+ is bonded in a 6-coordinate geometry to four V2+ and two equivalent Si4- atoms. There are a spread of V–V bond distances ranging from 2.33–2.50 Å. Both V–Si bond lengths are 2.47 Å. In the third V2+ site, V2+ is bonded in a 6-coordinate geometry to four equivalent V2+ and two equivalent Si4- atoms. Both V–Si bond lengths are 2.47 Å. There are two inequivalent W2+ sites. In the first W2+ site, W2+ is bonded in a 7-coordinate geometry to seven Si4- atoms. There are a spread of W–Si bond distances ranging from 2.81–2.91 Å. In the second W2+ site, W2+ is bonded to five Si4- atoms to form distorted WSi5 trigonal bipyramids that share corners with six SiV4Si2W6 cuboctahedra, corners with six equivalent WSi5 trigonal bipyramids, edges with four equivalent SiV2Si4W6 cuboctahedra, and an edgeedge with one WSi5 trigonal bipyramid. There are a spread of W–Si bond distances ranging from 2.79–2.86 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded to four V2+, six W2+, and two equivalent Si4- atoms to form distorted SiV4Si2W6 cuboctahedra that share corners with four equivalent SiV2Si4W6 cuboctahedra, corners with four equivalent WSi5 trigonal bipyramids, edges with six equivalent SiV4Si2W6 cuboctahedra, and faces with eight SiV4Si2W6 cuboctahedra. Both Si–Si bond lengths are 2.55 Å. In the second Si4- site, Si4- is bonded to two equivalent V2+, six W2+, and four Si4- atoms to form distorted SiV2Si4W6 cuboctahedra that share corners with eight SiV4Si2W6 cuboctahedra, corners with two equivalent WSi5 trigonal bipyramids, edges with two equivalent SiV2Si4W6 cuboctahedra, edges with four equivalent WSi5 trigonal bipyramids, and faces with ten SiV4Si2W6 cuboctahedra. There are one shorter (2.37 Å) and one longer (2.52 Å) Si–Si bond lengths.

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2020-05-02. Materials Data on VSiW by Materials Project. https://doi.org/10.17188/1721063

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