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DOE OSTI · 1752088

Materials Data on Ta6V3Fe3C2 by Materials Project

Abstract

Ta6V3Fe3C2 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are six inequivalent Ta sites. In the first Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent V, four Fe, and two equivalent C atoms. Both Ta–V bond lengths are 2.81 Å. There are two shorter (2.87 Å) and two longer (2.89 Å) Ta–Fe bond lengths. Both Ta–C bond lengths are 2.17 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to four V, two equivalent Fe, and two equivalent C atoms. There are two shorter (2.78 Å) and two longer (2.99 Å) Ta–V bond lengths. Both Ta–Fe bond lengths are 2.92 Å. Both Ta–C bond lengths are 2.19 Å. In the third Ta site, Ta is bonded in a distorted bent 150 degrees geometry to three V, three Fe, and two C atoms. There are a spread of Ta–V bond distances ranging from 2.78–2.92 Å. There are a spread of Ta–Fe bond distances ranging from 2.93–2.96 Å. Both Ta–C bond lengths are 2.18 Å. In the fourth Ta site, Ta is bonded in a distorted bent 150 degrees geometry to four V, two equivalent Fe, and two equivalent C atoms. There are two shorter (2.80 Å) and two longer (2.98 Å) Ta–V bond lengths. Both Ta–Fe bond lengths are 2.99 Å. Both Ta–C bond lengths are 2.18 Å. In the fifth Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent V, four Fe, and two equivalent C atoms. Both Ta–V bond lengths are 2.93 Å. There are two shorter (2.78 Å) and two longer (2.94 Å) Ta–Fe bond lengths. Both Ta–C bond lengths are 2.18 Å. In the sixth Ta site, Ta is bonded in a distorted bent 150 degrees geometry to three V, three Fe, and two C atoms. There are one shorter (2.85 Å) and two longer (2.96 Å) Ta–V bond lengths. There are a spread of Ta–Fe bond distances ranging from 2.75–2.97 Å. There are one shorter (2.17 Å) and one longer (2.18 Å) Ta–C bond lengths. There are three inequivalent V sites. In the first V site, V is bonded to six Ta, one V, and five Fe atoms to form distorted VTa6VFe5 cuboctahedra that share a cornercorner with one VTa6VFe5 cuboctahedra, corners with five FeTa6V4Fe2 cuboctahedra, corners with three equivalent CTa6 octahedra, a faceface with one VTa6VFe5 cuboctahedra, faces with six FeTa6V5Fe cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedra tilt angles range from 44–45°. The V–V bond length is 2.57 Å. There are three shorter (2.45 Å) and two longer (2.58 Å) V–Fe bond lengths. In the second V site, V is bonded in a 12-coordinate geometry to six Ta, three V, and three Fe atoms. There are one shorter (2.58 Å) and two longer (2.59 Å) V–V bond lengths. There are two shorter (2.47 Å) and one longer (2.49 Å) V–Fe bond lengths. In the third V site, V is bonded in a 12-coordinate geometry to six Ta, three V, and three Fe atoms. The V–V bond length is 2.57 Å. There are one shorter (2.46 Å) and two longer (2.48 Å) V–Fe bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six Ta, five V, and one Fe atom to form distorted FeTa6V5Fe cuboctahedra that share corners with three equivalent FeTa6V2Fe4 cuboctahedra, edges with six CTa6 octahedra, faces with two equivalent VTa6VFe5 cuboctahedra, and faces with eight FeTa6V5Fe cuboctahedra. The Fe–Fe bond length is 2.50 Å. In the second Fe site, Fe is bonded to six Ta, four V, and two equivalent Fe atoms to form distorted FeTa6V4Fe2 cuboctahedra that share corners with three equivalent VTa6VFe5 cuboctahedra, edges with six CTa6 octahedra, faces with two equivalent VTa6VFe5 cuboctahedra, and faces with eight FeTa6V5Fe cuboctahedra. Both Fe–Fe bond lengths are 2.47 Å. In the third Fe site, Fe is bonded to six Ta, two equivalent V, and four Fe atoms to form distorted FeTa6V2Fe4 cuboctahedra that share corners with two equivalent VTa6VFe5 cuboctahedra, corners with four FeTa6V5Fe cuboctahedra, corners with three equivalent CTa6 octahedra, faces with two equivalent VTa6VFe5 cuboctahedra, faces with five FeTa6V5Fe cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedra tilt angles range from 41–42°. The Fe–Fe bond length is 2.59 Å. There are two inequivalent C sites. In the first C site, C is bonded to six Ta atoms to form CTa6 octahedra that share corners with three equivalent FeTa6V2Fe4 cuboctahedra, corners with six CTa6 octahedra, edges with six FeTa6V5Fe cuboctahedra, a faceface with one FeTa6V2Fe4 cuboctahedra, and faces with two equivalent VTa6VFe5 cuboctahedra. The corner-sharing octahedra tilt angles range from 39–44°. In the second C site, C is bonded to six Ta atoms to form CTa6 octahedra that share corners with three equivalent VTa6VFe5 cuboctahedra, corners with six CTa6 octahedra, edges with six FeTa6V5Fe cuboctahedra, a faceface with one VTa6VFe5 cuboctahedra, and faces with two equivalent FeTa6V2Fe4 cuboctahedra. The corner-sharing octahedra tilt angles range from 40–42°.

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2020-05-02. Materials Data on Ta6V3Fe3C2 by Materials Project. https://doi.org/10.17188/1752088

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