Materials Data on HfTa2VC4 by Materials Project

Abstract

HfTa2VC4 is alpha Po-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Hf4+ is bonded to six C4- atoms to form HfC6 octahedra that share corners with three equivalent TaC6 octahedra, corners with three equivalent VC6 octahedra, edges with three equivalent TaC6 octahedra, edges with three equivalent VC6 octahedra, and edges with six equivalent HfC6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are three shorter (2.26 Å) and three longer (2.30 Å) Hf–C bond lengths. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six C4- atoms to form TaC6 octahedra that share corners with three equivalent TaC6 octahedra, corners with three equivalent VC6 octahedra, edges with three equivalent VC6 octahedra, and edges with nine TaC6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are three shorter (2.21 Å) and three longer (2.25 Å) Ta–C bond lengths. In the second Ta5+ site, Ta5+ is bonded to six C4- atoms to form TaC6 octahedra that share corners with three equivalent HfC6 octahedra, corners with three equivalent TaC6 octahedra, edges with three equivalent HfC6 octahedra, and edges with nine TaC6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. All Ta–C bond lengths are 2.23 Å. V2+ is bonded to six C4- atoms to form VC6 octahedra that share corners with three equivalent HfC6 octahedra, corners with three equivalent TaC6 octahedra, edges with three equivalent HfC6 octahedra, edges with three equivalent TaC6 octahedra, and edges with six equivalent VC6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are three shorter (2.15 Å) and three longer (2.16 Å) V–C bond lengths. There are four inequivalent C4- sites. In the first C4- site, C4- is bonded to three equivalent Hf4+ and three equivalent Ta5+ atoms to form CHf3Ta3 octahedra that share corners with six CTa6 octahedra and edges with twelve CHf3Ta3 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second C4- site, C4- is bonded to six Ta5+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the third C4- site, C4- is bonded to three equivalent Hf4+ and three equivalent V2+ atoms to form a mixture of corner and edge-sharing CHf3V3 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the fourth C4- site, C4- is bonded to three equivalent Ta5+ and three equivalent V2+ atoms to form a mixture of corner and edge-sharing CTa3V3 octahedra. The corner-sharing octahedra tilt angles range from 0–1°.