Materials Data on Sm2HfS5 by Materials Project

Abstract

Sm2HfS5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Sm3+ 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. Hf4+ is bonded to seven S2- atoms to form distorted edge-sharing HfS7 pentagonal bipyramids. There are a spread of Hf–S bond distances ranging from 2.53–2.70 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Sm3+ and two equivalent Hf4+ atoms to form distorted SSm2Hf2 trigonal pyramids that share corners with four equivalent SSm4Hf square pyramids, corners with four SSm4Hf trigonal bipyramids, corners with six equivalent SSm2Hf2 trigonal pyramids, an edgeedge with one SSm4Hf square pyramid, edges with four SSm4Hf trigonal bipyramids, and an edgeedge with one SSm2Hf2 trigonal pyramid. In the second S2- site, S2- is bonded to four equivalent Sm3+ and one Hf4+ atom to form distorted SSm4Hf trigonal bipyramids that share corners with five equivalent SSm4Hf square pyramids, corners with five SSm4Hf trigonal bipyramids, corners with four equivalent SSm2Hf2 trigonal pyramids, edges with two equivalent SSm4Hf square pyramids, edges with four equivalent SSm4Hf trigonal bipyramids, and edges with four equivalent SSm2Hf2 trigonal pyramids. In the third S2- site, S2- is bonded to four equivalent Sm3+ and one Hf4+ atom to form distorted SSm4Hf square pyramids that share corners with nine SSm4Hf trigonal bipyramids, corners with eight equivalent SSm2Hf2 trigonal pyramids, edges with two equivalent SSm4Hf square pyramids, edges with three SSm4Hf trigonal bipyramids, edges with two equivalent SSm2Hf2 trigonal pyramids, and a faceface with one SSm4Hf trigonal bipyramid. In the fourth S2- site, S2- is bonded to four equivalent Sm3+ and one Hf4+ atom to form distorted SSm4Hf trigonal bipyramids that share corners with four equivalent SSm4Hf square pyramids, corners with five SSm4Hf trigonal bipyramids, corners with four equivalent SSm2Hf2 trigonal pyramids, an edgeedge with one SSm4Hf square pyramid, edges with four equivalent SSm4Hf trigonal bipyramids, edges with four equivalent SSm2Hf2 trigonal pyramids, and a faceface with one SSm4Hf square pyramid.