Materials Data on Cr8Fe2CuNiS16 by Materials Project

Cr8Fe2NiCuS16 is Spinel-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent FeS4 tetrahedra, corners with three equivalent CuS4 tetrahedra, and edges with six CrS6 octahedra. There are three shorter (2.36 Å) and three longer (2.41 Å) Cr–S bond lengths. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent FeS4 tetrahedra, corners with three equivalent NiS4 tetrahedra, and edges with six CrS6 octahedra. There are three shorter (2.36 Å) and three longer (2.42 Å) Cr–S bond lengths. In the third Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one CuS4 tetrahedra, corners with two equivalent NiS4 tetrahedra, corners with three FeS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.35–2.42 Å. In the fourth Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one NiS4 tetrahedra, corners with two equivalent CuS4 tetrahedra, corners with three FeS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.35–2.42 Å. There are two inequivalent Fe+2.50+ sites. In the first Fe+2.50+ site, Fe+2.50+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Fe–S bond lengths are 2.16 Å. In the second Fe+2.50+ site, Fe+2.50+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Fe–S bond lengths are 2.16 Å. Ni2+ is bonded to four S2- atoms to form NiS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 55–56°. All Ni–S bond lengths are 2.19 Å. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. All Cu–S bond lengths are 2.24 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Cu1+ atom. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Ni2+ atom. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Cu1+ atom. In the fourth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Ni2+ atom. In the fifth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Fe+2.50+ atom. In the sixth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Fe+2.50+ atom. In the seventh S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Fe+2.50+ atom. In the eighth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Fe+2.50+ atom.