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DOE OSTI · 1701246

Materials Data on Ta10Si2MoSe8 by Materials Project

Abstract

Ta10MoSi2Se8 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are five inequivalent Ta sites. In the first Ta site, Ta is bonded in a 5-coordinate geometry to two equivalent Si and three Se atoms. Both Ta–Si bond lengths are 2.55 Å. There are one shorter (2.65 Å) and two longer (2.70 Å) Ta–Se bond lengths. In the second Ta site, Ta is bonded in a 7-coordinate geometry to two equivalent Mo, two equivalent Si, and three Se atoms. Both Ta–Mo bond lengths are 2.91 Å. Both Ta–Si bond lengths are 2.56 Å. There are one shorter (2.66 Å) and two longer (2.71 Å) Ta–Se bond lengths. In the third Ta site, Ta is bonded in a 5-coordinate geometry to one Si and four Se atoms. The Ta–Si bond length is 2.76 Å. There are a spread of Ta–Se bond distances ranging from 2.63–2.82 Å. In the fourth Ta site, Ta is bonded in a 7-coordinate geometry to two equivalent Mo, two equivalent Si, and three Se atoms. Both Ta–Mo bond lengths are 2.89 Å. Both Ta–Si bond lengths are 2.56 Å. There are one shorter (2.55 Å) and two longer (2.69 Å) Ta–Se bond lengths. In the fifth Ta site, Ta is bonded in a 5-coordinate geometry to one Si and four Se atoms. The Ta–Si bond length is 2.78 Å. There are two shorter (2.64 Å) and two longer (2.72 Å) Ta–Se bond lengths. Mo is bonded to eight Ta, two equivalent Si, and two equivalent Se atoms to form face-sharing MoTa8Si2Se2 cuboctahedra. Both Mo–Si bond lengths are 2.72 Å. Both Mo–Se bond lengths are 2.74 Å. Si is bonded in a 9-coordinate geometry to eight Ta and one Mo atom. There are four inequivalent Se sites. In the first Se site, Se is bonded in a 4-coordinate geometry to four Ta atoms. In the second Se site, Se is bonded in a distorted T-shaped geometry to three Ta atoms. In the third Se site, Se is bonded in a 6-coordinate geometry to six Ta atoms. In the fourth Se site, Se is bonded in a 5-coordinate geometry to four Ta and one Mo atom.

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2020-04-29. Materials Data on Ta10Si2MoSe8 by Materials Project. https://doi.org/10.17188/1701246

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36 MATERIALS SCIENCE↗