Materials Data on Cr2AgS4 by Materials Project

Cr2AgS4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. 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 corners with three equivalent CrS6 octahedra, corners with four equivalent AgS7 pentagonal bipyramids, edges with six CrS6 octahedra, and an edgeedge with one AgS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 52–59°. There are a spread of Cr–S bond distances ranging from 2.37–2.48 Å. In the second Cr+3.50+ site, Cr+3.50+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent CrS6 octahedra, corners with four equivalent AgS7 pentagonal bipyramids, edges with four CrS6 octahedra, and edges with four equivalent AgS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 52–59°. There are a spread of Cr–S bond distances ranging from 2.35–2.47 Å. Ag1+ is bonded to seven S2- atoms to form distorted AgS7 pentagonal bipyramids that share corners with eight CrS6 octahedra, edges with five CrS6 octahedra, edges with two equivalent AgS7 pentagonal bipyramids, and faces with two equivalent AgS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–66°. There are a spread of Ag–S bond distances ranging from 2.72–2.82 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent Cr+3.50+ and three equivalent Ag1+ atoms. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Cr+3.50+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to three Cr+3.50+ and two equivalent Ag1+ atoms. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to three Cr+3.50+ and two equivalent Ag1+ atoms.