Materials Data on Sm2ThS5 by Materials Project

Abstract

ThSm2S5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Th4+ is bonded to seven S2- atoms to form distorted edge-sharing ThS7 pentagonal bipyramids. There are a spread of Th–S bond distances ranging from 2.72–2.90 Å. Sm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Sm–S bond distances ranging from 2.84–3.10 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Th4+ and two equivalent Sm3+ atoms to form distorted SSm2Th2 trigonal pyramids that share corners with six SSm4Th square pyramids, corners with two equivalent SSm4Th trigonal bipyramids, corners with six equivalent SSm2Th2 trigonal pyramids, edges with three SSm4Th square pyramids, edges with two equivalent SSm4Th trigonal bipyramids, and an edgeedge with one SSm2Th2 trigonal pyramid. In the second S2- site, S2- is bonded to one Th4+ and four equivalent Sm3+ atoms to form distorted SSm4Th trigonal bipyramids that share corners with six SSm4Th square pyramids, corners with four equivalent SSm4Th trigonal bipyramids, corners with four equivalent SSm2Th2 trigonal pyramids, edges with six SSm4Th square pyramids, and edges with four equivalent SSm2Th2 trigonal pyramids. In the third S2- site, S2- is bonded to one Th4+ and four equivalent Sm3+ atoms to form SSm4Th square pyramids that share corners with four equivalent SSm4Th square pyramids, corners with five equivalent SSm4Th trigonal bipyramids, corners with eight equivalent SSm2Th2 trigonal pyramids, edges with three SSm4Th square pyramids, edges with two equivalent SSm4Th trigonal bipyramids, edges with two equivalent SSm2Th2 trigonal pyramids, and a faceface with one SSm4Th square pyramid. In the fourth S2- site, S2- is bonded to one Th4+ and four equivalent Sm3+ atoms to form distorted SSm4Th square pyramids that share corners with eight SSm4Th square pyramids, a cornercorner with one SSm4Th trigonal bipyramid, corners with four equivalent SSm2Th2 trigonal pyramids, an edgeedge with one SSm4Th square pyramid, edges with four equivalent SSm4Th trigonal bipyramids, edges with four equivalent SSm2Th2 trigonal pyramids, and a faceface with one SSm4Th square pyramid.