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DOE OSTI · 1710505

Materials Data on Ho5Cu(WO4)8 by Materials Project

Abstract

Ho5Cu(WO4)8 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with seven WO6 octahedra, an edgeedge with one HoO6 octahedra, an edgeedge with one WO6 octahedra, and an edgeedge with one HoO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 28–54°. There are a spread of Ho–O bond distances ranging from 2.25–2.43 Å. In the second Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with seven WO6 octahedra, an edgeedge with one WO6 octahedra, an edgeedge with one HoO7 pentagonal bipyramid, and an edgeedge with one CuO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 35–54°. There are a spread of Ho–O bond distances ranging from 2.26–2.42 Å. In the third Ho3+ site, Ho3+ is bonded to six O2- atoms to form distorted HoO6 octahedra that share corners with eight WO6 octahedra and edges with two equivalent HoO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 47–61°. There are a spread of Ho–O bond distances ranging from 2.21–2.34 Å. There are four inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share a cornercorner with one HoO6 octahedra, corners with two equivalent WO6 octahedra, corners with three HoO7 pentagonal bipyramids, an edgeedge with one WO6 octahedra, and an edgeedge with one HoO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 13–60°. There are a spread of W–O bond distances ranging from 1.83–2.17 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with two equivalent WO6 octahedra, corners with three HoO7 pentagonal bipyramids, a cornercorner with one CuO6 pentagonal pyramid, an edgeedge with one WO6 octahedra, and an edgeedge with one HoO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 15°. There are a spread of W–O bond distances ranging from 1.82–2.19 Å. In the third W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with two equivalent HoO6 octahedra, corners with four HoO7 pentagonal bipyramids, a cornercorner with one CuO6 pentagonal pyramid, and edges with two WO6 octahedra. The corner-sharing octahedra tilt angles range from 50–61°. There are a spread of W–O bond distances ranging from 1.79–2.14 Å. In the fourth W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share a cornercorner with one HoO6 octahedra, corners with four HoO7 pentagonal bipyramids, corners with two equivalent CuO6 pentagonal pyramids, and edges with two WO6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of W–O bond distances ranging from 1.80–2.17 Å. Cu1+ is bonded to six O2- atoms to form distorted CuO6 pentagonal pyramids that share corners with eight WO6 octahedra and edges with two equivalent HoO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 44–63°. There are two shorter (2.10 Å) and four longer (2.43 Å) Cu–O bond lengths. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Ho3+ and two W6+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ho3+ and two W6+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ho3+, one W6+, and one Cu1+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ho3+ and one W6+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ho3+ and one W6+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ho3+, one W6+, and one Cu1+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ho3+ and two W6+ atoms. In the twelfth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ho3+ and two W6+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent W6+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent W6+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two W6+ and one Cu1+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ho3+ and two W6+ atoms.

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2020-04-30. Materials Data on Ho5Cu(WO4)8 by Materials Project. https://doi.org/10.17188/1710505

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