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DOE OSTI · 1748164

Materials Data on Ho3Sc2S7 by Materials Project

Abstract

Ho3Sc2S7 crystallizes in the monoclinic Cm 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 four equivalent HoS6 octahedra, corners with four ScS6 octahedra, an edgeedge with one HoS6 octahedra, edges with three equivalent ScS6 octahedra, edges with two equivalent HoS7 pentagonal bipyramids, and faces with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–66°. There are a spread of Ho–S bond distances ranging from 2.72–2.89 Å. In the second Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with two equivalent HoS6 octahedra, corners with six ScS6 octahedra, edges with four ScS6 octahedra, edges with two equivalent HoS7 pentagonal bipyramids, and faces with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 23–70°. There are a spread of Ho–S bond distances ranging from 2.74–2.91 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three ScS6 octahedra, corners with six HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, edges with three equivalent ScS6 octahedra, and an edgeedge with one HoS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 2–50°. There are a spread of Ho–S bond distances ranging from 2.65–2.75 Å. There are two inequivalent Sc+2.50+ sites. In the first Sc+2.50+ site, Sc+2.50+ is bonded to six S2- atoms to form ScS6 octahedra that share a cornercorner with one ScS6 octahedra, corners with two equivalent HoS6 octahedra, corners with six HoS7 pentagonal bipyramids, edges with two equivalent ScS6 octahedra, edges with three equivalent HoS6 octahedra, and an edgeedge with one HoS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 2–51°. There are a spread of Sc–S bond distances ranging from 2.55–2.70 Å. In the second Sc+2.50+ site, Sc+2.50+ is bonded to six S2- atoms to form ScS6 octahedra that share a cornercorner with one HoS6 octahedra, a cornercorner with one ScS6 octahedra, corners with four HoS7 pentagonal bipyramids, edges with two equivalent ScS6 octahedra, and edges with six HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 50–51°. There are two shorter (2.55 Å) and four longer (2.63 Å) Sc–S bond lengths. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ho3+ and one Sc+2.50+ atom to form distorted SHo3Sc tetrahedra that share corners with three SHo3Sc tetrahedra, corners with nine SHo3Sc2 trigonal bipyramids, and edges with four SHo4Sc trigonal bipyramids. In the second S2- site, S2- is bonded to two equivalent Ho3+ and two Sc+2.50+ atoms to form distorted SHo2Sc2 tetrahedra that share corners with three SHo3Sc tetrahedra, corners with nine SHo3Sc2 trigonal bipyramids, and edges with four SHo3Sc2 trigonal bipyramids. In the third S2- site, S2- is bonded to three Ho3+ and two equivalent Sc+2.50+ atoms to form distorted SHo3Sc2 trigonal bipyramids that share corners with five SHo3Sc tetrahedra, corners with four SHo3Sc2 trigonal bipyramids, an edgeedge with one SHo2Sc2 tetrahedra, and edges with five SHo3Sc2 trigonal bipyramids. In the fourth S2- site, S2- is bonded to four Ho3+ and one Sc+2.50+ atom to form distorted SHo4Sc trigonal bipyramids that share corners with five SHo3Sc tetrahedra, corners with four SHo3Sc2 trigonal bipyramids, an edgeedge with one SHo3Sc tetrahedra, and edges with five SHo3Sc2 trigonal bipyramids. In the fifth S2- site, S2- is bonded to three Ho3+ and two equivalent Sc+2.50+ atoms to form distorted SHo3Sc2 trigonal bipyramids that share corners with four equivalent SHo3Sc tetrahedra, corners with six SHo3Sc2 trigonal bipyramids, edges with three SHo3Sc tetrahedra, and edges with six SHo4Sc trigonal bipyramids. In the sixth S2- site, S2- is bonded to three Ho3+ and two equivalent Sc+2.50+ atoms to form distorted SHo3Sc2 trigonal bipyramids that share corners with four equivalent SHo2Sc2 tetrahedra, corners with six SHo3Sc2 trigonal bipyramids, edges with three SHo3Sc tetrahedra, and edges with six SHo3Sc2 trigonal bipyramids. In the seventh S2- site, S2- is bonded in a rectangular see-saw-like geometry to two equivalent Ho3+ and two equivalent Sc+2.50+ atoms.

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2020-05-02. Materials Data on Ho3Sc2S7 by Materials Project. https://doi.org/10.17188/1748164

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