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DOE OSTI · 1718527

Materials Data on Ta6Cr3Fe3C2 by Materials Project

Abstract

Ta6Cr3Fe3C2 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 Fe, and two equivalent C atoms. There are two shorter (2.88 Å) and two longer (2.89 Å) Ta–Cr bond lengths. Both Ta–Fe bond lengths are 2.81 Å. Both Ta–C bond lengths are 2.19 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent Cr, four Fe, and two equivalent C atoms. Both Ta–Cr bond lengths are 2.89 Å. There are two shorter (2.83 Å) and two longer (2.87 Å) Ta–Fe bond lengths. Both Ta–C bond lengths are 2.16 Å. In the third Ta site, Ta is bonded in a distorted bent 150 degrees geometry to three Cr, three Fe, and two C atoms. There are one shorter (2.88 Å) and two longer (2.89 Å) Ta–Cr bond lengths. There are a spread of Ta–Fe bond distances ranging from 2.81–2.90 Å. There are one shorter (2.17 Å) and one longer (2.18 Å) Ta–C bond lengths. In the fourth Ta site, Ta is bonded in a 2-coordinate geometry to two equivalent Cr, four Fe, and two equivalent C atoms. Both Ta–Cr bond lengths are 2.88 Å. There are two shorter (2.79 Å) and two longer (2.89 Å) Ta–Fe 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 Fe, and two equivalent C atoms. There are two shorter (2.80 Å) and two longer (2.89 Å) Ta–Cr bond lengths. Both Ta–Fe bond lengths are 2.89 Å. Both Ta–C bond lengths are 2.18 Å. In the sixth Ta site, Ta is bonded in a 2-coordinate geometry to three Cr, three Fe, 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–Fe 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 Fe atoms to form distorted CrTa6CrFe5 cuboctahedra that share corners with three equivalent CrTa6Cr4Fe2 cuboctahedra, corners with three equivalent FeTa6Cr3Fe3 cuboctahedra, edges with six CTa6 octahedra, faces with four FeTa6Cr3Fe3 cuboctahedra, and faces with eight CrTa6CrFe5 cuboctahedra. The Cr–Cr bond length is 2.45 Å. There are a spread of Cr–Fe bond distances ranging from 2.42–2.45 Å. In the second Cr site, Cr is bonded to six Ta, two equivalent Cr, and four Fe atoms to form distorted CrTa6Cr2Fe4 cuboctahedra that share corners with three equivalent FeTa6Cr3Fe3 cuboctahedra, edges with six CTa6 octahedra, faces with four FeTa6Cr3Fe3 cuboctahedra, and faces with eight CrTa6CrFe5 cuboctahedra. Both Cr–Cr bond lengths are 2.45 Å. There are a spread of Cr–Fe bond distances ranging from 2.42–2.47 Å. In the third Cr site, Cr is bonded to six Ta, four Cr, and two equivalent Fe atoms to form distorted CrTa6Cr4Fe2 cuboctahedra that share corners with three equivalent FeTa6Cr3Fe3 cuboctahedra, corners with four CrTa6CrFe5 cuboctahedra, corners with three equivalent CTa6 octahedra, faces with five CrTa6CrFe5 cuboctahedra, faces with six FeTa6Cr3Fe3 cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedral tilt angles are 43°. The Cr–Cr bond length is 2.52 Å. Both Cr–Fe bond lengths are 2.53 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to six Ta, five Cr, and one Fe atom. The Fe–Fe bond length is 2.52 Å. In the second Fe site, Fe is bonded to six Ta, three Cr, and three Fe atoms to form distorted FeTa6Cr3Fe3 cuboctahedra that share corners with three FeTa6Cr3Fe3 cuboctahedra, corners with six CrTa6CrFe5 cuboctahedra, corners with three equivalent CTa6 octahedra, faces with three FeTa6Cr3Fe3 cuboctahedra, faces with six CrTa6CrFe5 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) Fe–Fe bond lengths. In the third Fe site, Fe is bonded to six Ta, three Cr, and three Fe atoms to form distorted FeTa6Cr3Fe3 cuboctahedra that share corners with three equivalent CrTa6Cr2Fe4 cuboctahedra, corners with three FeTa6Cr3Fe3 cuboctahedra, corners with three equivalent CTa6 octahedra, faces with three FeTa6Cr3Fe3 cuboctahedra, faces with eight CrTa6CrFe5 cuboctahedra, and faces with three CTa6 octahedra. The corner-sharing octahedral tilt angles are 43°. The Fe–Fe bond length is 2.47 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 CrTa6Cr4Fe2 cuboctahedra, corners with three equivalent FeTa6Cr3Fe3 cuboctahedra, corners with six CTa6 octahedra, edges with six CrTa6CrFe5 cuboctahedra, a faceface with one CrTa6Cr4Fe2 cuboctahedra, and faces with three FeTa6Cr3Fe3 cuboctahedra. The corner-sharing octahedral tilt angles are 43°. In the second C site, C is bonded to six Ta atoms to form CTa6 octahedra that share corners with three equivalent FeTa6Cr3Fe3 cuboctahedra, corners with six CTa6 octahedra, edges with six CrTa6CrFe5 cuboctahedra, faces with two equivalent CrTa6Cr4Fe2 cuboctahedra, and faces with three FeTa6Cr3Fe3 cuboctahedra. The corner-sharing octahedral tilt angles are 43°.

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2020-05-02. Materials Data on Ta6Cr3Fe3C2 by Materials Project. https://doi.org/10.17188/1718527

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