Materials Data on Ca(CrS2)4 by Materials Project

Abstract

Ca(CrS2)4 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Ca2+ is bonded to six equivalent S2- atoms to form distorted CaS6 octahedra that share corners with six equivalent CrS6 octahedra and edges with six equivalent CrS6 octahedra. The corner-sharing octahedral tilt angles are 10°. All Ca–S bond lengths are 2.82 Å. There are two inequivalent Cr+3.50+ sites. In the first Cr+3.50+ site, Cr+3.50+ is bonded to six S2- atoms to form CrS6 octahedra that share edges with two equivalent CaS6 octahedra and edges with six CrS6 octahedra. There are two shorter (2.38 Å) and four longer (2.40 Å) Cr–S bond lengths. In the second Cr+3.50+ site, Cr+3.50+ is bonded to six equivalent S2- atoms to form CrS6 octahedra that share corners with six equivalent CaS6 octahedra and edges with six equivalent CrS6 octahedra. The corner-sharing octahedral tilt angles are 10°. All Cr–S bond lengths are 2.37 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Cr+3.50+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Cr+3.50+ atoms.