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DOE OSTI · 1714337

Materials Data on Ho4US7 by Materials Project

Abstract

UHo4S7 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 HoS6 octahedra, corners with six HoS7 pentagonal bipyramids, edges with two equivalent US6 octahedra, edges with three equivalent HoS6 octahedra, and an edgeedge with one HoS7 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 Ho sites. In the first Ho site, Ho is bonded to seven S atoms to form distorted HoS7 pentagonal bipyramids that share corners with four equivalent US6 octahedra, corners with four HoS6 octahedra, an edgeedge with one US6 octahedra, edges with three equivalent 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 22–65°. There are a spread of Ho–S bond distances ranging from 2.73–2.95 Å. In the second Ho site, Ho is bonded to seven S atoms to form distorted HoS7 pentagonal bipyramids that share corners with two equivalent US6 octahedra, corners with six 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 22–68°. There are a spread of Ho–S bond distances ranging from 2.72–2.96 Å. In the third Ho site, Ho is bonded to six S atoms to form HoS6 octahedra that share a cornercorner with one US6 octahedra, a cornercorner with one HoS6 octahedra, corners with four HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, and edges with six HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Ho–S bond distances ranging from 2.66–2.73 Å. In the fourth Ho site, Ho is bonded to six S atoms to form HoS6 octahedra that share a cornercorner with one HoS6 octahedra, corners with two equivalent US6 octahedra, corners with six HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, edges with three equivalent US6 octahedra, and an edgeedge with one HoS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 1–57°. There are a spread of Ho–S bond distances ranging from 2.68–2.79 Å. There are seven inequivalent S sites. In the first S site, S is bonded to one U and four Ho atoms to form SHo4U trigonal bipyramids that share corners with five SHo3U tetrahedra, corners with four SHo5 trigonal bipyramids, an edgeedge with one SHo4 tetrahedra, and edges with five SHo4U trigonal bipyramids. In the second S site, S is bonded to two equivalent U and three Ho atoms to form SHo3U2 trigonal bipyramids that share corners with five SHo3U tetrahedra, corners with four SHo5 trigonal bipyramids, an edgeedge with one SHo3U tetrahedra, and edges with five SHo4U trigonal bipyramids. In the third S site, S is bonded to five Ho atoms to form distorted SHo5 trigonal bipyramids that share corners with four equivalent SHo3U tetrahedra, corners with six SHo4U trigonal bipyramids, edges with three SHo3U tetrahedra, and edges with six SHo3U2 trigonal bipyramids. In the fourth 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 SHo4U trigonal bipyramids, edges with three SHo3U tetrahedra, and edges with six SHo4U trigonal bipyramids. In the fifth S site, S is bonded to one U and three Ho atoms to form distorted SHo3U tetrahedra that share corners with three SHo3U tetrahedra, corners with nine SHo4U trigonal bipyramids, and edges with four SHo3U2 trigonal bipyramids. In the sixth S site, S is bonded to four Ho atoms to form distorted SHo4 tetrahedra that share corners with three SHo3U tetrahedra, corners with nine SHo4U trigonal bipyramids, and edges with four SHo4U trigonal bipyramids. In the seventh S site, S is bonded in a rectangular see-saw-like geometry to two equivalent U and two equivalent Ho atoms.

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2020-05-03. Materials Data on Ho4US7 by Materials Project. https://doi.org/10.17188/1714337

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