DOI: 10.17188/1729083
title: Materials Data on Sm4(ErS2)11 by Materials Project

description: Sm4(ErS2)11 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are six inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to seven S2- atoms to form distorted ErS7 pentagonal bipyramids that share corners with three ErS6 octahedra, edges with two equivalent ErS6 octahedra, and edges with four equivalent ErS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–50°. There are a spread of Er–S bond distances ranging from 2.69–2.88 Å. In the second Er3+ site, Er3+ is bonded to six S2- atoms to form a mixture of corner and edge-sharing ErS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Er–S bond distances ranging from 2.61–2.77 Å. In the third Er3+ site, Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share corners with three equivalent ErS6 octahedra, corners with two equivalent ErS7 pentagonal bipyramids, and edges with four ErS6 octahedra. The corner-sharing octahedra tilt angles range from 52–62°. There are a spread of Er–S bond distances ranging from 2.64–2.79 Å. In the fourth Er3+ site, Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share corners with three equivalent ErS6 octahedra, a cornercorner with one ErS7 pentagonal bipyramid, edges with four equivalent ErS6 octahedra, and edges with two equivalent ErS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 52–62°. There are a spread of Er–S bond distances ranging from 2.65–2.76 Å. In the fifth Er3+ site, Er3+ is bonded to six S2- atoms to form a mixture of corner and edge-sharing ErS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Er–S bond distances ranging from 2.63–2.76 Å. In the sixth Er3+ site, Er3+ is bonded to six S2- atoms to form a mixture of corner and edge-sharing ErS6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are two shorter (2.72 Å) and four longer (2.73 Å) Er–S bond lengths. There are two inequivalent Sm+2.75+ sites. In the first Sm+2.75+ site, Sm+2.75+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.87–3.02 Å. In the second Sm+2.75+ site, Sm+2.75+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.87–3.47 Å. There are eleven inequivalent S2- sites. In the first S2- site, S2- is bonded to three Er3+ and two equivalent Sm+2.75+ atoms to form distorted SSm2Er3 trigonal bipyramids that share corners with four SSm2Er3 trigonal bipyramids, corners with two SSmEr3 trigonal pyramids, edges with six SSm2Er3 trigonal bipyramids, and edges with two equivalent SEr4 trigonal pyramids. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Er3+ atoms. In the third S2- site, S2- is bonded in a 3-coordinate geometry to three Er3+ and one Sm+2.75+ atom. In the fourth S2- site, S2- is bonded to three Er3+ and two equivalent Sm+2.75+ atoms to form distorted SSm2Er3 trigonal bipyramids that share corners with six SSm2Er3 trigonal bipyramids, corners with two equivalent SSmEr3 trigonal pyramids, edges with two equivalent SSm2Er3 square pyramids, edges with four SSm2Er3 trigonal bipyramids, and an edgeedge with one SSmEr3 trigonal pyramid. In the fifth S2- site, S2- is bonded to three Er3+ and two equivalent Sm+2.75+ atoms to form distorted SSm2Er3 square pyramids that share corners with two equivalent SSm2Er3 square pyramids, corners with four SSm3Er2 trigonal bipyramids, edges with three SSm2Er3 square pyramids, edges with three SSm2Er3 trigonal bipyramids, and edges with two equivalent SSmEr3 trigonal pyramids. In the sixth S2- site, S2- is bonded to three Er3+ and two equivalent Sm+2.75+ atoms to form distorted SSm2Er3 square pyramids that share corners with four SSm2Er3 square pyramids, corners with two equivalent SSm3Er2 trigonal bipyramids, corners with two equivalent SSmEr3 trigonal pyramids, edges with four SSm2Er3 square pyramids, and edges with three SSm3Er2 trigonal bipyramids. In the seventh S2- site, S2- is bonded to two equivalent Er3+ and three Sm+2.75+ atoms to form distorted SSm3Er2 trigonal bipyramids that share corners with four SSm2Er3 square pyramids, corners with two equivalent SSm2Er3 trigonal bipyramids, corners with four equivalent SEr4 trigonal pyramids, edges with two SSm2Er3 square pyramids, edges with six SSm2Er3 trigonal bipyramids, and edges with three SSmEr3 trigonal pyramids. In the eighth S2- site, S2- is bonded to three Er3+ and one Sm+2.75+ atom to form distorted SSmEr3 trigonal pyramids that share corners with two equivalent SSm2Er3 square pyramids, corners with four SSm2Er3 trigonal bipyramids, corners with five SSmEr3 trigonal pyramids, edges with two equivalent SSm2Er3 square pyramids, and edges with three SSm3Er2 trigonal bipyramids. In the ninth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Er3+ atoms. In the tenth S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 trigonal pyramids that share corners with five SSm2Er3 trigonal bipyramids, corners with five SSmEr3 trigonal pyramids, edges with three SSm2Er3 trigonal bipyramids, and edges with two equivalent SEr4 trigonal pyramids. In the eleventh S2- site, S2- is bonded to two equivalent Er3+ and three Sm+2.75+ atoms to form distorted SSm3Er2 trigonal bipyramids that share corners with two equivalent SSm2Er3 square pyramids, corners with four SSm2Er3 trigonal bipyramids, a cornercorner with one SSmEr3 trigonal pyramid, edges with two equivalent SSm2Er3 square pyramids, and edges with six SSm2Er3 trigonal bipyramids.