Materials Data on Ca2SnS4 by Materials Project

Abstract

Ca2SnS4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ca2+ is bonded to seven S2- atoms to form distorted CaS7 pentagonal bipyramids that share corners with six equivalent CaS7 pentagonal bipyramids, corners with three equivalent SnS4 tetrahedra, edges with three equivalent CaS7 pentagonal bipyramids, edges with two equivalent SnS4 tetrahedra, and faces with two equivalent CaS7 pentagonal bipyramids. There are a spread of Ca–S bond distances ranging from 2.89–3.03 Å. Sn4+ is bonded to four S2- atoms to form SnS4 tetrahedra that share corners with six equivalent CaS7 pentagonal bipyramids and edges with four equivalent CaS7 pentagonal bipyramids. There are three shorter (2.42 Å) and one longer (2.43 Å) Sn–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to four equivalent Ca2+ and one Sn4+ atom to form a mixture of distorted edge and corner-sharing SCa4Sn trigonal bipyramids. In the second S2- site, S2- is bonded to four equivalent Ca2+ and one Sn4+ atom to form a mixture of distorted edge and corner-sharing SCa4Sn trigonal bipyramids. In the third S2- site, S2- is bonded in a see-saw-like geometry to three equivalent Ca2+ and one Sn4+ atom.