Materials Data on CaSnS3 by Materials Project

Abstract

CaSnS3 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. there are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight S2- atoms. There are a spread of Ca–S bond distances ranging from 2.89–3.26 Å. In the second Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight S2- atoms. There are a spread of Ca–S bond distances ranging from 2.92–3.11 Å. In the third Ca2+ site, Ca2+ is bonded to six S2- atoms to form CaS6 octahedra that share corners with six SnS4 tetrahedra. There are four shorter (2.80 Å) and two longer (2.82 Å) Ca–S bond lengths. There are four inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to six S2- atoms to form corner-sharing SnS6 octahedra. There are four shorter (2.58 Å) and two longer (2.60 Å) Sn–S bond lengths. In the second Sn4+ site, Sn4+ is bonded to four equivalent S2- atoms to form SnS4 tetrahedra that share corners with four equivalent CaS6 octahedra. The corner-sharing octahedral tilt angles are 62°. All Sn–S bond lengths are 2.41 Å. In the third Sn4+ site, Sn4+ is bonded to four equivalent S2- atoms to form corner-sharing SnS4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. All Sn–S bond lengths are 2.44 Å. In the fourth Sn4+ site, Sn4+ is bonded to four S2- atoms to form SnS4 tetrahedra that share corners with two equivalent CaS6 octahedra and corners with two equivalent SnS6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Sn–S bond distances ranging from 2.38–2.47 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ca2+ and one Sn4+ atom to form distorted SCa3Sn tetrahedra that share corners with eleven SCa3Sn tetrahedra, corners with two equivalent SCa2Sn2 trigonal pyramids, edges with two SCa3Sn tetrahedra, and an edgeedge with one SCa2Sn2 trigonal pyramid. In the second S2- site, S2- is bonded to three Ca2+ and one Sn4+ atom to form distorted SCa3Sn tetrahedra that share corners with ten SCa3Sn tetrahedra, a cornercorner with one SCa2Sn2 trigonal pyramid, edges with three SCa3Sn tetrahedra, and an edgeedge with one SCa2Sn2 trigonal pyramid. In the third S2- site, S2- is bonded to two Ca2+ and two Sn4+ atoms to form distorted SCa2Sn2 trigonal pyramids that share corners with nine SCa3Sn tetrahedra, corners with two equivalent SCa2Sn2 trigonal pyramids, and edges with three SCa3Sn tetrahedra. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to two Ca2+ and two Sn4+ atoms. In the fifth S2- site, S2- is bonded to two equivalent Ca2+ and two Sn4+ atoms to form distorted SCa2Sn2 tetrahedra that share corners with nine SCa3Sn tetrahedra, corners with three equivalent SCa2Sn2 trigonal pyramids, edges with two equivalent SCa3Sn tetrahedra, and an edgeedge with one SCa2Sn2 trigonal pyramid. In the sixth S2- site, S2- is bonded to three Ca2+ and one Sn4+ atom to form distorted SCa3Sn tetrahedra that share corners with nine SCa3Sn tetrahedra, corners with three equivalent SCa2Sn2 trigonal pyramids, and edges with four SCa2Sn2 tetrahedra.