DOI: 10.17188/1312982
title: Materials Data on Er2S3 by Materials Project

description: Er2S3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are four inequivalent Er3+ sites. In the first 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 equivalent ErS6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Er–S bond distances ranging from 2.64–2.75 Å. In the second Er3+ site, Er3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Er–S bond distances ranging from 2.78–3.00 Å. In the third 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 37–51°. There are a spread of Er–S bond distances ranging from 2.67–2.92 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 octahedral tilt angles are 59°. There are a spread of Er–S bond distances ranging from 2.65–2.75 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded to five Er3+ atoms to form distorted SEr5 trigonal bipyramids that share corners with four equivalent SEr5 square pyramids, corners with two equivalent SEr5 trigonal bipyramids, a cornercorner with one SEr4 trigonal pyramid, an edgeedge with one SEr5 square pyramid, edges with seven SEr5 trigonal bipyramids, and edges with two equivalent SEr4 trigonal pyramids. In the second S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 trigonal pyramids that share corners with two equivalent SEr5 square pyramids, corners with four SEr5 trigonal bipyramids, corners with four SEr4 trigonal pyramids, edges with three equivalent SEr5 square pyramids, and edges with two equivalent SEr5 trigonal bipyramids. In the third S2- site, S2- is bonded in a 4-coordinate geometry to four Er3+ atoms. In the fourth S2- site, S2- is bonded to five Er3+ atoms to form distorted SEr5 square pyramids that share corners with six SEr5 trigonal bipyramids, corners with five SEr4 trigonal pyramids, edges with four equivalent SEr5 square pyramids, edges with two SEr5 trigonal bipyramids, and edges with three equivalent SEr4 trigonal pyramids. In the fifth S2- site, S2- is bonded to five Er3+ atoms to form distorted SEr5 trigonal bipyramids that share corners with two equivalent SEr5 square pyramids, corners with two equivalent SEr5 trigonal bipyramids, corners with seven SEr4 trigonal pyramids, an edgeedge with one SEr5 square pyramid, edges with five SEr5 trigonal bipyramids, and an edgeedge with one SEr4 trigonal pyramid. In the sixth S2- site, S2- is bonded to four Er3+ atoms to form distorted SEr4 trigonal pyramids that share corners with three equivalent SEr5 square pyramids, corners with four equivalent SEr5 trigonal bipyramids, corners with four SEr4 trigonal pyramids, an edgeedge with one SEr5 trigonal bipyramid, and edges with two equivalent SEr4 trigonal pyramids.