Materials Data on Ho5S7 by Materials Project

Abstract

Ho5S7 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded to six S atoms to form HoS6 octahedra that share corners with two equivalent HoS6 octahedra, corners with four equivalent HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, and edges with six equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are two shorter (2.67 Å) and four longer (2.73 Å) Ho–S bond lengths. In the second Ho site, Ho is bonded to six S atoms to form HoS6 octahedra that share corners with three HoS6 octahedra, corners with six equivalent HoS7 pentagonal bipyramids, edges with five equivalent HoS6 octahedra, and an edgeedge with one HoS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 0–56°. There are a spread of Ho–S bond distances ranging from 2.67–2.82 Å. In the third Ho site, Ho is bonded to seven S atoms to form distorted HoS7 pentagonal bipyramids that share corners with eight HoS6 octahedra, edges with four HoS6 octahedra, edges with two equivalent HoS7 pentagonal bipyramids, and faces with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–67°. There are a spread of Ho–S bond distances ranging from 2.73–2.92 Å. There are four inequivalent S sites. In the first S site, S is bonded in a square co-planar geometry to four equivalent Ho atoms. In the second S site, S is bonded to five Ho atoms to form distorted SHo5 trigonal bipyramids that share corners with four equivalent SHo4 tetrahedra, corners with six SHo5 trigonal bipyramids, edges with three equivalent SHo4 tetrahedra, and edges with six SHo5 trigonal bipyramids. In the third S site, S is bonded to four Ho atoms to form distorted SHo4 tetrahedra that share corners with three equivalent SHo4 tetrahedra, corners with nine SHo5 trigonal bipyramids, and edges with four SHo5 trigonal bipyramids. In the fourth S site, S is bonded to five Ho atoms to form SHo5 trigonal bipyramids that share corners with five equivalent SHo4 tetrahedra, corners with four equivalent SHo5 trigonal bipyramids, an edgeedge with one SHo4 tetrahedra, and edges with five SHo5 trigonal bipyramids.