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DOE OSTI · 1714705

Materials Data on Ta6Cr3Cu3C2 by Materials Project

Abstract

Ta6Cr3Cu3C2 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 Cu, and two equivalent C atoms. There are two shorter (2.80 Å) and two longer (2.95 Å) Ta–Cr bond lengths. Both Ta–Cu bond lengths are 2.74 Å. Both Ta–C bond lengths are 2.21 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent Cr, four Cu, and two equivalent C atoms. Both Ta–Cr bond lengths are 3.00 Å. There are two shorter (2.77 Å) and two longer (2.90 Å) Ta–Cu bond lengths. Both Ta–C bond lengths are 2.15 Å. In the third Ta site, Ta is bonded in a 2-coordinate geometry to three Cr, three Cu, and two C atoms. There are a spread of Ta–Cr bond distances ranging from 2.86–2.94 Å. There are a spread of Ta–Cu bond distances ranging from 2.75–2.92 Å. There are one shorter (2.17 Å) and one longer (2.19 Å) Ta–C bond lengths. In the fourth Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent Cr, four Cu, and two equivalent C atoms. Both Ta–Cr bond lengths are 3.01 Å. There are two shorter (2.74 Å) and two longer (2.92 Å) Ta–Cu bond lengths. 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 four Cr, two equivalent Cu, and two equivalent C atoms. There are two shorter (2.84 Å) and two longer (2.87 Å) Ta–Cr bond lengths. Both Ta–Cu bond lengths are 2.92 Å. Both Ta–C bond lengths are 2.17 Å. In the sixth Ta site, Ta is bonded in a distorted bent 150 degrees geometry to three Cr, three Cu, and two C atoms. There are a spread of Ta–Cr bond distances ranging from 2.83–2.97 Å. There are a spread of Ta–Cu bond distances ranging from 2.75–2.94 Å. There are one shorter (2.17 Å) and one longer (2.18 Å) Ta–C bond lengths. There are three inequivalent Cr sites. In the first Cr site, Cr is bonded to six Ta, one Cr, and five Cu atoms to form distorted CrTa6CrCu5 cuboctahedra that share corners with three equivalent CrTa6Cr4Cu2 cuboctahedra, edges with six CTa6 octahedra, and faces with eight CrTa6CrCu5 cuboctahedra. The Cr–Cr bond length is 2.37 Å. There are a spread of Cr–Cu bond distances ranging from 2.47–2.53 Å. In the second Cr site, Cr is bonded to six Ta, two equivalent Cr, and four Cu atoms to form distorted CrTa6Cr2Cu4 cuboctahedra that share edges with six CTa6 octahedra and faces with eight CrTa6CrCu5 cuboctahedra. Both Cr–Cr bond lengths are 2.34 Å. There are a spread of Cr–Cu bond distances ranging from 2.48–2.58 Å. In the third Cr site, Cr is bonded to six Ta, four Cr, and two equivalent Cu atoms to form CrTa6Cr4Cu2 cuboctahedra that share corners with four CrTa6CrCu5 cuboctahedra, corners with three equivalent CTa6 octahedra, faces with five CrTa6CrCu5 cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedra tilt angles range from 43–44°. The Cr–Cr bond length is 2.50 Å. Both Cr–Cu bond lengths are 2.57 Å. There are three inequivalent Cu sites. In the first Cu site, Cu is bonded in a 12-coordinate geometry to six Ta, five Cr, and one Cu atom. The Cu–Cu bond length is 2.64 Å. In the second Cu site, Cu is bonded in a 12-coordinate geometry to six Ta, three Cr, and three Cu atoms. There are two shorter (2.65 Å) and one longer (2.66 Å) Cu–Cu bond lengths. In the third Cu site, Cu is bonded in a 12-coordinate geometry to six Ta, three Cr, and three Cu atoms. The Cu–Cu bond length is 2.63 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 CrTa6Cr4Cu2 cuboctahedra, corners with six CTa6 octahedra, edges with six CrTa6CrCu5 cuboctahedra, and a faceface with one CrTa6Cr4Cu2 cuboctahedra. The corner-sharing octahedra tilt angles range from 41–44°. 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 CrTa6CrCu5 cuboctahedra, and faces with two equivalent CrTa6Cr4Cu2 cuboctahedra. The corner-sharing octahedra tilt angles range from 41–43°.

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2020-05-02. Materials Data on Ta6Cr3Cu3C2 by Materials Project. https://doi.org/10.17188/1714705

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