Materials Data on AlCr4GaC2 by Materials Project

Abstract

Cr4GaAlC2 is H-Phase-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are two inequivalent Cr sites. In the first Cr site, Cr is bonded in a 3-coordinate geometry to three equivalent Ga and three equivalent C atoms. All Cr–Ga bond lengths are 2.65 Å. All Cr–C bond lengths are 1.97 Å. In the second Cr site, Cr is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Cr–Al bond lengths are 2.66 Å. All Cr–C bond lengths are 1.96 Å. Ga is bonded to six equivalent Cr and six equivalent Ga atoms to form distorted GaCr6Ga6 cuboctahedra that share corners with six equivalent GaCr6Ga6 cuboctahedra, corners with six equivalent CCr6 octahedra, edges with six equivalent GaCr6Ga6 cuboctahedra, edges with six equivalent CCr6 octahedra, and faces with six equivalent GaCr6Ga6 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. All Ga–Ga bond lengths are 2.85 Å. Al is bonded to six equivalent Cr and six equivalent Al atoms to form AlAl6Cr6 cuboctahedra that share corners with six equivalent AlAl6Cr6 cuboctahedra, corners with six equivalent CCr6 octahedra, edges with six equivalent AlAl6Cr6 cuboctahedra, edges with six equivalent CCr6 octahedra, and faces with six equivalent AlAl6Cr6 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. All Al–Al bond lengths are 2.85 Å. C is bonded to six Cr atoms to form CCr6 octahedra that share corners with three equivalent GaCr6Ga6 cuboctahedra, corners with three equivalent AlAl6Cr6 cuboctahedra, edges with three equivalent GaCr6Ga6 cuboctahedra, edges with three equivalent AlAl6Cr6 cuboctahedra, and edges with six equivalent CCr6 octahedra.