Materials Data on Tm5S7 by Materials Project

Abstract

Tm5S7 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Tm sites. In the first Tm site, Tm is bonded to six S atoms to form TmS6 octahedra that share corners with two equivalent TmS6 octahedra, corners with four equivalent TmS7 pentagonal bipyramids, edges with two equivalent TmS6 octahedra, and edges with six equivalent TmS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are two shorter (2.65 Å) and four longer (2.70 Å) Tm–S bond lengths. In the second Tm site, Tm is bonded to six S atoms to form TmS6 octahedra that share corners with three TmS6 octahedra, corners with six equivalent TmS7 pentagonal bipyramids, edges with five equivalent TmS6 octahedra, and an edgeedge with one TmS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 0–56°. There are a spread of Tm–S bond distances ranging from 2.64–2.78 Å. In the third Tm site, Tm is bonded to seven S atoms to form distorted TmS7 pentagonal bipyramids that share corners with eight TmS6 octahedra, edges with four TmS6 octahedra, edges with two equivalent TmS7 pentagonal bipyramids, and faces with two equivalent TmS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–67°. There are a spread of Tm–S bond distances ranging from 2.70–2.90 Å. There are four inequivalent S sites. In the first S site, S is bonded in a square co-planar geometry to four equivalent Tm atoms. In the second S site, S is bonded to five Tm atoms to form distorted STm5 trigonal bipyramids that share corners with four equivalent STm4 tetrahedra, corners with six STm5 trigonal bipyramids, edges with three equivalent STm4 tetrahedra, and edges with six STm5 trigonal bipyramids. In the third S site, S is bonded to four Tm atoms to form distorted STm4 tetrahedra that share corners with three equivalent STm4 tetrahedra, corners with nine STm5 trigonal bipyramids, and edges with four STm5 trigonal bipyramids. In the fourth S site, S is bonded to five Tm atoms to form STm5 trigonal bipyramids that share corners with five equivalent STm4 tetrahedra, corners with four equivalent STm5 trigonal bipyramids, an edgeedge with one STm4 tetrahedra, and edges with five STm5 trigonal bipyramids.