DOI: 10.17188/1662377
title: Materials Data on Tm4US7 by Materials Project

description: UTm4S7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. U is bonded to six S atoms to form US6 octahedra that share corners with three TmS6 octahedra, corners with six TmS7 pentagonal bipyramids, edges with two equivalent US6 octahedra, edges with three equivalent TmS6 octahedra, and an edgeedge with one TmS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 1–56°. There are a spread of U–S bond distances ranging from 2.70–2.82 Å. There are four inequivalent Tm sites. In the first Tm site, Tm is bonded to seven S atoms to form distorted TmS7 pentagonal bipyramids that share corners with four equivalent US6 octahedra, corners with four TmS6 octahedra, an edgeedge with one US6 octahedra, edges with three equivalent 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 22–64°. There are a spread of Tm–S bond distances ranging from 2.71–2.92 Å. In the second Tm site, Tm is bonded to seven S atoms to form distorted TmS7 pentagonal bipyramids that share corners with two equivalent US6 octahedra, corners with six 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 21–68°. There are a spread of Tm–S bond distances ranging from 2.70–2.93 Å. In the third Tm site, Tm is bonded to six S atoms to form TmS6 octahedra that share a cornercorner with one TmS6 octahedra, corners with two equivalent US6 octahedra, corners with six TmS7 pentagonal bipyramids, edges with two equivalent TmS6 octahedra, edges with three equivalent US6 octahedra, and an edgeedge with one TmS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 1–57°. There are a spread of Tm–S bond distances ranging from 2.65–2.77 Å. In the fourth Tm site, Tm is bonded to six S atoms to form TmS6 octahedra that share a cornercorner with one US6 octahedra, a cornercorner with one TmS6 octahedra, corners with four TmS7 pentagonal bipyramids, edges with two equivalent TmS6 octahedra, and edges with six TmS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Tm–S bond distances ranging from 2.64–2.71 Å. There are seven inequivalent S sites. In the first S site, S is bonded to one U and four Tm atoms to form STm4U trigonal bipyramids that share corners with five STm3U tetrahedra, corners with four STm5 trigonal bipyramids, an edgeedge with one STm4 tetrahedra, and edges with five STm4U trigonal bipyramids. In the second S site, S is bonded to two equivalent U and three Tm atoms to form STm3U2 trigonal bipyramids that share corners with five STm3U tetrahedra, corners with four STm5 trigonal bipyramids, an edgeedge with one STm3U tetrahedra, and edges with five STm4U trigonal bipyramids. In the third S site, S is bonded to one U and three Tm atoms to form distorted STm3U tetrahedra that share corners with three STm3U tetrahedra, corners with nine STm4U trigonal bipyramids, and edges with four STm5 trigonal bipyramids. In the fourth S site, S is bonded to four Tm atoms to form distorted STm4 tetrahedra that share corners with three STm3U tetrahedra, corners with nine STm4U trigonal bipyramids, and edges with four STm5 trigonal bipyramids. In the fifth S site, S is bonded in a rectangular see-saw-like geometry to two equivalent U and two equivalent Tm atoms. In the sixth S site, S is bonded to five Tm atoms to form distorted STm5 trigonal bipyramids that share corners with four equivalent STm3U tetrahedra, corners with six STm5 trigonal bipyramids, edges with three STm3U tetrahedra, and edges with six STm3U2 trigonal bipyramids. In the seventh 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 STm4U trigonal bipyramids, edges with three STm3U tetrahedra, and edges with six STm4U trigonal bipyramids.