Materials Data on CdAg2Sn3S8 by Materials Project

Abstract

Ag2CdSn3S8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Ag1+ is bonded to four S2- atoms to form AgS4 tetrahedra that share corners with three equivalent CdS6 octahedra and corners with nine equivalent SnS6 octahedra. The corner-sharing octahedra tilt angles range from 56–60°. There are three shorter (2.52 Å) and one longer (2.60 Å) Ag–S bond lengths. Cd2+ is bonded to six equivalent S2- atoms to form CdS6 octahedra that share corners with six equivalent AgS4 tetrahedra and edges with six equivalent SnS6 octahedra. All Cd–S bond lengths are 2.70 Å. Sn4+ is bonded to six S2- atoms to form SnS6 octahedra that share corners with six equivalent AgS4 tetrahedra, edges with two equivalent CdS6 octahedra, and edges with four equivalent SnS6 octahedra. There are four shorter (2.59 Å) and two longer (2.67 Å) Sn–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to one Ag1+ and three equivalent Sn4+ atoms. In the second S2- site, S2- is bonded to one Ag1+, one Cd2+, and two equivalent Sn4+ atoms to form a mixture of distorted corner and edge-sharing SCdAgSn2 trigonal pyramids.