DOI: 10.17188/1745700
title: Materials Data on Sm9Ga5S21 by Materials Project

description: Sm9Ga5S21 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are six inequivalent Sm3+ sites. In the first Sm3+ site, Sm3+ is bonded to seven S2- atoms to form distorted SmS7 pentagonal bipyramids that share corners with three SmS7 pentagonal bipyramids, corners with two GaS4 tetrahedra, edges with two SmS7 pentagonal bipyramids, an edgeedge with one GaS4 tetrahedra, and a faceface with one GaS6 octahedra. There are a spread of Sm–S bond distances ranging from 2.83–2.96 Å. In the second Sm3+ site, Sm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.80–3.31 Å. In the third Sm3+ site, Sm3+ is bonded to seven S2- atoms to form distorted SmS7 pentagonal bipyramids that share a cornercorner with one GaS6 octahedra, corners with three SmS7 pentagonal bipyramids, corners with two GaS4 tetrahedra, an edgeedge with one SmS7 pentagonal bipyramid, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Sm–S bond distances ranging from 2.81–2.98 Å. In the fourth Sm3+ site, Sm3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Sm–S bond distances ranging from 2.79–3.04 Å. In the fifth Sm3+ site, Sm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.81–3.31 Å. In the sixth Sm3+ site, Sm3+ is bonded to seven S2- atoms to form distorted SmS7 pentagonal bipyramids that share a cornercorner with one GaS6 octahedra, corners with four SmS7 pentagonal bipyramids, corners with two GaS4 tetrahedra, an edgeedge with one SmS7 pentagonal bipyramid, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedral tilt angles are 37°. There are a spread of Sm–S bond distances ranging from 2.82–2.99 Å. There are six inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three SmS7 pentagonal bipyramids and edges with two SmS7 pentagonal bipyramids. There are a spread of Ga–S bond distances ranging from 2.26–2.30 Å. In the second Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three SmS7 pentagonal bipyramids and an edgeedge with one SmS7 pentagonal bipyramid. There are a spread of Ga–S bond distances ranging from 2.26–2.31 Å. In the third Ga3+ site, Ga3+ is bonded to six S2- atoms to form GaS6 octahedra that share corners with three equivalent SmS7 pentagonal bipyramids and faces with three equivalent SmS7 pentagonal bipyramids. There are three shorter (2.50 Å) and three longer (2.51 Å) Ga–S bond lengths. In the fourth Ga3+ site, Ga3+ is bonded in a 3-coordinate geometry to six S2- atoms. There are three shorter (2.27 Å) and three longer (2.97 Å) Ga–S bond lengths. In the fifth Ga3+ site, Ga3+ is bonded in a distorted trigonal non-coplanar geometry to six S2- atoms. There are three shorter (2.27 Å) and three longer (2.99 Å) Ga–S bond lengths. In the sixth Ga3+ site, Ga3+ is bonded to six S2- atoms to form GaS6 octahedra that share corners with three equivalent SmS7 pentagonal bipyramids. There are three shorter (2.49 Å) and three longer (2.51 Å) Ga–S bond lengths. There are fourteen inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Sm3+ and one Ga3+ atom. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Sm3+ and one Ga3+ atom. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Sm3+ and one Ga3+ atom. In the fourth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Sm3+ and one Ga3+ atom. In the fifth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Sm3+ and one Ga3+ atom. In the sixth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Sm3+ and one Ga3+ atom. In the seventh S2- site, S2- is bonded to three Sm3+ and one Ga3+ atom to form distorted SSm3Ga tetrahedra that share corners with three SSm3Ga2 square pyramids and corners with three SSm3Ga trigonal pyramids. In the eighth S2- site, S2- is bonded to three Sm3+ and one Ga3+ atom to form distorted SSm3Ga tetrahedra that share corners with three SSm3Ga2 square pyramids and corners with three SSm3Ga trigonal pyramids. In the ninth S2- site, S2- is bonded in a 5-coordinate geometry to four Sm3+ and one Ga3+ atom. In the tenth S2- site, S2- is bonded to three Sm3+ and two Ga3+ atoms to form distorted SSm3Ga2 square pyramids that share corners with three SSm3Ga tetrahedra, a cornercorner with one SSm3Ga trigonal pyramid, edges with two equivalent SSm3Ga trigonal pyramids, and faces with two equivalent SSm3Ga2 square pyramids. In the eleventh S2- site, S2- is bonded to three Sm3+ and one Ga3+ atom to form distorted SSm3Ga trigonal pyramids that share a cornercorner with one SSm3Ga2 square pyramid, corners with three SSm3Ga tetrahedra, edges with two equivalent SSm3Ga2 square pyramids, and edges with two equivalent SSm3Ga trigonal pyramids. In the twelfth S2- site, S2- is bonded to three Sm3+ and two Ga3+ atoms to form distorted SSm3Ga2 square pyramids that share corners with three SSm3Ga tetrahedra, a cornercorner with one SSm3Ga trigonal pyramid, edges with two equivalent SSm3Ga trigonal pyramids, and faces with two equivalent SSm3Ga2 square pyramids. In the thirteenth S2- site, S2- is bonded to three Sm3+ and one Ga3+ atom to form distorted SSm3Ga trigonal pyramids that share a cornercorner with one SSm3Ga2 square pyramid, corners with three SSm3Ga tetrahedra, edges with two equivalent SSm3Ga2 square pyramids, and edges with two equivalent SSm3Ga trigonal pyramids. In the fourteenth S2- site, S2- is bonded in a 5-coordinate geometry to four Sm3+ and one Ga3+ atom.