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DOE OSTI · 1722631

Materials Data on La(HoS2)3 by Materials Project

Abstract

La(HoS2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with three HoS6 octahedra, edges with two equivalent HoS6 octahedra, and edges with four equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–51°. There are a spread of Ho–S bond distances ranging from 2.70–2.93 Å. In the second Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, a cornercorner with one HoS7 pentagonal bipyramid, edges with four equivalent HoS6 octahedra, and edges with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Ho–S bond distances ranging from 2.68–2.78 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, and edges with four equivalent HoS6 octahedra. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Ho–S bond distances ranging from 2.66–2.80 Å. La3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.94–3.08 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Ho3+ atoms. In the second S2- site, S2- is bonded to three Ho3+ and one La3+ atom to form distorted SLaHo3 trigonal pyramids that share corners with two equivalent SLa2Ho3 square pyramids, corners with four SLa2Ho3 trigonal bipyramids, corners with two equivalent SLaHo3 trigonal pyramids, edges with three equivalent SLa2Ho3 square pyramids, and edges with two equivalent SLa3Ho2 trigonal bipyramids. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Ho3+ atoms. In the fourth S2- site, S2- is bonded to three equivalent Ho3+ and two equivalent La3+ atoms to form distorted SLa2Ho3 square pyramids that share corners with six SLa2Ho3 trigonal bipyramids, corners with two equivalent SLaHo3 trigonal pyramids, edges with four equivalent SLa2Ho3 square pyramids, edges with two SLa2Ho3 trigonal bipyramids, and edges with three equivalent SLaHo3 trigonal pyramids. In the fifth S2- site, S2- is bonded to three Ho3+ and two equivalent La3+ atoms to form distorted SLa2Ho3 trigonal bipyramids that share corners with two equivalent SLa2Ho3 square pyramids, corners with two equivalent SLa3Ho2 trigonal bipyramids, corners with three equivalent SLaHo3 trigonal pyramids, an edgeedge with one SLa2Ho3 square pyramid, and edges with five SLa2Ho3 trigonal bipyramids. In the sixth S2- site, S2- is bonded to two equivalent Ho3+ and three equivalent La3+ atoms to form distorted SLa3Ho2 trigonal bipyramids that share corners with four equivalent SLa2Ho3 square pyramids, corners with two equivalent SLa2Ho3 trigonal bipyramids, a cornercorner with one SLaHo3 trigonal pyramid, an edgeedge with one SLa2Ho3 square pyramid, edges with seven SLa2Ho3 trigonal bipyramids, and edges with two equivalent SLaHo3 trigonal pyramids.

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BibTeXRIS

2020-05-03. Materials Data on La(HoS2)3 by Materials Project. https://doi.org/10.17188/1722631

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