Ca2Sn3S8 is beta indium sulfide-derived structured and crystallizes in the trigonal R-3m space group. Ca(1) is bonded to six equivalent S(1) atoms to form distorted CaS6 pentagonal pyramids that share corners with six equivalent Sn(1)S6 octahedra, edges with three equivalent Sn(1)S6 octahedra, and edges with three equivalent Ca(1)S6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 51°. Sn(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form SnS6 octahedra that share corners with four equivalent Ca(1)S6 pentagonal pyramids, edges with four equivalent Sn(1)S6 octahedra, and edges with two equivalent Ca(1)S6 pentagonal pyramids. There are two inequivalent S sites. In the first S site, S(2) is bonded in a distorted T-shaped geometry to three equivalent Sn(1) atoms. In the second S site, S(1) is bonded to two equivalent Ca(1) and two equivalent Sn(1) atoms to form a mixture of corner and edge-sharing SCa2Sn2 trigonal pyramids.
Ca2Sn3S8 is beta indium sulfide-derived structured and crystallizes in the trigonal R-3m space group. Ca(1) is bonded to six equivalent S(1) atoms to form distorted CaS6 pentagonal pyramids that share corners with six equivalent Sn(1)S6 octahedra, edges with three equivalent Sn(1)S6 octahedra, and edges with three equivalent Ca(1)S6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 51°. There are three shorter (2.82 Å) and three longer (2.88 Å) Ca(1)-S(1) bond lengths. Sn(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form SnS6 octahedra that share corners with four equivalent Ca(1)S6 pentagonal pyramids, edges with four equivalent Sn(1)S6 octahedra, and edges with two equivalent Ca(1)S6 pentagonal pyramids. Both Sn(1)-S(2) bond lengths are 2.62 Å. All Sn(1)-S(1) bond lengths are 2.59 Å. There are two inequivalent S sites. In the first S site, S(2) is bonded in a distorted T-shaped geometry to three equivalent Sn(1) atoms. In the second S site, S(1) is bonded to two equivalent Ca(1) and two equivalent Sn(1) atoms to form a mixture of corner and edge-sharing SCa2Sn2 trigonal pyramids.