Materials Data on CaSn2S5 by Materials Project

Abstract

CaSn2S5 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Ca–S bond distances ranging from 2.94–3.14 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to six S2- atoms to form SnS6 octahedra that share corners with four equivalent SnS5 square pyramids and edges with two equivalent SnS6 octahedra. There are a spread of Sn–S bond distances ranging from 2.55–2.62 Å. In the second Sn4+ site, Sn4+ is bonded to five S2- atoms to form SnS5 square pyramids that share corners with four equivalent SnS6 octahedra and an edgeedge with one SnS5 square pyramid. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Sn–S bond distances ranging from 2.48–2.55 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Ca2+ and two Sn4+ atoms to form a mixture of distorted edge and corner-sharing SCa2Sn2 tetrahedra. In the second S2- site, S2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two equivalent Sn4+ atoms. In the third S2- site, S2- is bonded to two equivalent Ca2+ and two equivalent Sn4+ atoms to form a mixture of distorted edge and corner-sharing SCa2Sn2 trigonal pyramids. In the fourth S2- site, S2- is bonded in a distorted trigonal planar geometry to three Sn4+ atoms.