Materials Data on KSnS2 by Materials Project

Abstract

KSnS2 is Caswellsilverite-like structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. K1+ is bonded to six S2- atoms to form distorted KS6 pentagonal pyramids that share corners with nine equivalent SnS6 octahedra, edges with three equivalent SnS6 octahedra, edges with six equivalent KS6 pentagonal pyramids, and a faceface with one SnS6 octahedra. The corner-sharing octahedra tilt angles range from 11–47°. There are three shorter (3.22 Å) and three longer (3.24 Å) K–S bond lengths. Sn3+ is bonded to six S2- atoms to form SnS6 octahedra that share corners with nine equivalent KS6 pentagonal pyramids, edges with six equivalent SnS6 octahedra, edges with three equivalent KS6 pentagonal pyramids, and a faceface with one KS6 pentagonal pyramid. There are three shorter (2.76 Å) and three longer (2.77 Å) Sn–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent K1+ and three equivalent Sn3+ atoms to form a mixture of distorted edge, face, and corner-sharing SK3Sn3 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 0–42°. In the second S2- site, S2- is bonded to three equivalent K1+ and three equivalent Sn3+ atoms to form a mixture of edge, face, and corner-sharing SK3Sn3 octahedra.