Materials Data on Ta8V(CS2)4 by Materials Project

Abstract

Ta8V(CS2)4 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Ta+3.75+ sites. In the first Ta+3.75+ site, Ta+3.75+ is bonded to three equivalent C4- and three equivalent S2- atoms to form TaC3S3 octahedra that share corners with three equivalent TaC3S3 octahedra, edges with nine equivalent TaC3S3 octahedra, and a faceface with one VS6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. All Ta–S bond lengths are 2.55 Å. In the second Ta+3.75+ site, Ta+3.75+ is bonded to three C4- and three S2- atoms to form TaC3S3 octahedra that share corners with two equivalent VS6 octahedra, corners with three equivalent TaC3S3 octahedra, and edges with nine TaC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–46°. All Ta–C bond lengths are 2.24 Å. There are one shorter (2.50 Å) and two longer (2.53 Å) Ta–S bond lengths. V2+ is bonded to six equivalent S2- atoms to form VS6 octahedra that share corners with twelve equivalent TaC3S3 octahedra and faces with two equivalent TaC3S3 octahedra. The corner-sharing octahedral tilt angles are 46°. All V–S bond lengths are 2.43 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.75+ atoms to form CTa6 octahedra that share corners with six equivalent STa3V trigonal pyramids, edges with six CTa6 octahedra, and edges with four equivalent STa3V trigonal pyramids. In the second C4- site, C4- is bonded to six equivalent Ta+3.75+ atoms to form CTa6 octahedra that share edges with six equivalent CTa6 octahedra and edges with six equivalent STa3V trigonal pyramids. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta+3.75+ atoms. In the second S2- site, S2- is bonded to three Ta+3.75+ and one V2+ atom to form distorted STa3V trigonal pyramids that share corners with three equivalent CTa6 octahedra, corners with five equivalent STa3V trigonal pyramids, edges with three CTa6 octahedra, and edges with two equivalent STa3V trigonal pyramids. The corner-sharing octahedral tilt angles are 10°.