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DOE OSTI · 1190692

Materials Data on Ta2PtSe7 by Materials Project

Abstract

Ta2PtSe7 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of two Ta2PtSe7 sheets oriented in the (1, 0, 0) direction. there are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Ta–Se bond distances ranging from 2.64–2.78 Å. In the second Ta5+ site, Ta5+ is bonded to six Se2- atoms to form TaSe6 octahedra that share edges with two equivalent PtSe6 octahedra and edges with four equivalent TaSe6 octahedra. There are a spread of Ta–Se bond distances ranging from 2.51–2.73 Å. Pt4+ is bonded to six Se2- atoms to form PtSe6 octahedra that share edges with two equivalent TaSe6 octahedra and edges with two equivalent PtSe6 octahedra. There are a spread of Pt–Se bond distances ranging from 2.53–2.72 Å. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to one Ta5+ and two equivalent Pt4+ atoms. In the second Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ta5+ atoms. In the third Se2- site, Se2- is bonded in a distorted L-shaped geometry to two equivalent Ta5+ atoms. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Ta5+ atoms. In the fifth Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Ta5+ and one Pt4+ atom. In the sixth Se2- site, Se2- is bonded in a 3-coordinate geometry to one Ta5+ and two equivalent Pt4+ atoms. In the seventh Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Ta5+ and one Pt4+ atom.

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2020-07-15. Materials Data on Ta2PtSe7 by Materials Project. https://doi.org/10.17188/1190692

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36 MATERIALS SCIENCE↗