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DOE OSTI · 1746778

Materials Data on Cr12Ga2(CoS8)3 by Materials Project

Abstract

Cr12Ga2(CoS8)3 is beta indium sulfide-derived structured and crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. there are three inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with two equivalent GaS4 tetrahedra, corners with three CoS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.35–2.44 Å. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one GaS4 tetrahedra, corners with five CoS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.37–2.41 Å. In the third Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one CoS4 tetrahedra, corners with three equivalent GaS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.33–2.46 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to four S2- atoms to form CoS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 54–58°. There are two shorter (2.25 Å) and two longer (2.26 Å) Co–S bond lengths. In the second Co2+ site, Co2+ is bonded to four equivalent S2- atoms to form CoS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. All Co–S bond lengths are 2.26 Å. Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are two shorter (2.30 Å) and two longer (2.33 Å) Ga–S bond lengths. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three Cr3+ atoms. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to three equivalent Cr3+ and one Co2+ atom. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Co2+ atom. In the fourth S2- site, S2- is bonded to three equivalent Cr3+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SCr3Ga tetrahedra. In the fifth S2- site, S2- is bonded to three Cr3+ and one Co2+ atom to form distorted SCr3Co trigonal pyramids that share corners with three equivalent SCr3Co trigonal pyramids and edges with three SCr3Ga trigonal pyramids. In the sixth S2- site, S2- is bonded to three Cr3+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SCr3Ga trigonal pyramids.

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2020-04-30. Materials Data on Cr12Ga2(CoS8)3 by Materials Project. https://doi.org/10.17188/1746778

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