DOI: 10.17188/1722645
title: Materials Data on Ta6Cr3Co3C2 by Materials Project

description: Ta6Cr3Co3C2 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 2-coordinate geometry to four Cr, two equivalent Co, and two equivalent C atoms. There are two shorter (2.87 Å) and two longer (2.88 Å) Ta–Cr bond lengths. Both Ta–Co bond lengths are 2.80 Å. Both Ta–C bond lengths are 2.18 Å. In the second Ta site, Ta is bonded in a 2-coordinate geometry to two equivalent Cr, four Co, and two equivalent C atoms. Both Ta–Cr bond lengths are 2.86 Å. There are two shorter (2.82 Å) and two longer (2.86 Å) Ta–Co bond lengths. Both Ta–C bond lengths are 2.16 Å. In the third Ta site, Ta is bonded in a 2-coordinate geometry to three Cr, three Co, and two C atoms. There are one shorter (2.87 Å) and two longer (2.88 Å) Ta–Cr bond lengths. There are a spread of Ta–Co bond distances ranging from 2.80–2.89 Å. Both Ta–C bond lengths are 2.17 Å. In the fourth Ta site, Ta is bonded in a 2-coordinate geometry to two equivalent Cr, four Co, and two equivalent C atoms. Both Ta–Cr bond lengths are 2.86 Å. There are two shorter (2.79 Å) and two longer (2.89 Å) Ta–Co bond lengths. Both Ta–C bond lengths are 2.17 Å. In the fifth Ta site, Ta is bonded in a distorted bent 150 degrees geometry to four Cr, two equivalent Co, and two equivalent C atoms. There are two shorter (2.81 Å) and two longer (2.90 Å) Ta–Cr bond lengths. Both Ta–Co bond lengths are 2.88 Å. Both Ta–C bond lengths are 2.17 Å. In the sixth Ta site, Ta is bonded in a 2-coordinate geometry to three Cr, three Co, and two C atoms. There are a spread of Ta–Cr bond distances ranging from 2.81–2.89 Å. There are one shorter (2.78 Å) and two longer (2.89 Å) Ta–Co bond lengths. Both Ta–C bond lengths are 2.17 Å. There are three inequivalent Cr sites. In the first Cr site, Cr is bonded to six Ta, one Cr, and five Co atoms to form distorted CrTa6CrCo5 cuboctahedra that share corners with three equivalent CrTa6Cr4Co2 cuboctahedra, corners with three equivalent CoTa6Cr3Co3 cuboctahedra, edges with six CTa6 octahedra, faces with two equivalent CoTa6Cr3Co3 cuboctahedra, and faces with eight CrTa6CrCo5 cuboctahedra. The Cr–Cr bond length is 2.45 Å. There are a spread of Cr–Co bond distances ranging from 2.40–2.45 Å. In the second Cr site, Cr is bonded to six Ta, two equivalent Cr, and four Co atoms to form distorted CrTa6Cr2Co4 cuboctahedra that share edges with six CTa6 octahedra, faces with two equivalent CoTa6Cr3Co3 cuboctahedra, and faces with eight CrTa6CrCo5 cuboctahedra. Both Cr–Cr bond lengths are 2.45 Å. There are a spread of Cr–Co bond distances ranging from 2.40–2.47 Å. In the third Cr site, Cr is bonded to six Ta, four Cr, and two equivalent Co atoms to form distorted CrTa6Cr4Co2 cuboctahedra that share corners with three equivalent CoTa6Cr3Co3 cuboctahedra, corners with four CrTa6CrCo5 cuboctahedra, corners with three equivalent CTa6 octahedra, faces with two equivalent CoTa6Cr3Co3 cuboctahedra, faces with five CrTa6CrCo5 cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedra tilt angles range from 42–43°. The Cr–Cr bond length is 2.49 Å. Both Cr–Co bond lengths are 2.50 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to six Ta, five Cr, and one Co atom. The Co–Co bond length is 2.49 Å. In the second Co site, Co is bonded to six Ta, three Cr, and three Co atoms to form distorted CoTa6Cr3Co3 cuboctahedra that share a cornercorner with one CoTa6Cr3Co3 cuboctahedra, corners with six CrTa6CrCo5 cuboctahedra, corners with three equivalent CTa6 octahedra, a faceface with one CoTa6Cr3Co3 cuboctahedra, faces with six CrTa6CrCo5 cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are one shorter (2.46 Å) and two longer (2.47 Å) Co–Co bond lengths. In the third Co site, Co is bonded in a 12-coordinate geometry to six Ta, three Cr, and three Co atoms. The Co–Co bond length is 2.49 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 CrTa6Cr4Co2 cuboctahedra, corners with three equivalent CoTa6Cr3Co3 cuboctahedra, corners with six CTa6 octahedra, edges with six CrTa6CrCo5 cuboctahedra, a faceface with one CrTa6Cr4Co2 cuboctahedra, and a faceface with one CoTa6Cr3Co3 cuboctahedra. The corner-sharing octahedra tilt angles range from 43–44°. In the second C site, C is bonded to six Ta atoms to form CTa6 octahedra that share corners with six CTa6 octahedra, edges with six CrTa6CrCo5 cuboctahedra, faces with two equivalent CrTa6Cr4Co2 cuboctahedra, and faces with two equivalent CoTa6Cr3Co3 cuboctahedra. The corner-sharing octahedra tilt angles range from 43–44°.