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DOE OSTI · 1684155

Materials Data on Ho4RuBr5 by Materials Project

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Abstract

Ho4RuBr5 crystallizes in the tetragonal P4_2/nnm space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded to three equivalent Ru and three Br atoms to form a mixture of corner and edge-sharing HoRu3Br3 octahedra. The corner-sharing octahedra tilt angles range from 2–15°. There are two shorter (2.81 Å) and one longer (2.83 Å) Ho–Ru bond lengths. There are one shorter (3.06 Å) and two longer (3.19 Å) Ho–Br bond lengths. In the second Ho site, Ho is bonded to one Ru and five Br atoms to form distorted HoRuBr5 octahedra that share corners with three HoRu3Br3 octahedra and edges with eight HoRuBr5 octahedra. The corner-sharing octahedra tilt angles range from 2–15°. The Ho–Ru bond length is 2.68 Å. There are a spread of Ho–Br bond distances ranging from 2.90–3.22 Å. In the third Ho site, Ho is bonded to one Ru and five Br atoms to form distorted HoRuBr5 octahedra that share a cornercorner with one HoRu3Br3 octahedra and edges with eight HoRuBr5 octahedra. The corner-sharing octahedral tilt angles are 14°. The Ho–Ru bond length is 2.70 Å. There are a spread of Ho–Br bond distances ranging from 2.92–3.19 Å. Ru is bonded to six Ho atoms to form distorted edge-sharing RuHo6 octahedra. There are four inequivalent Br sites. In the first Br site, Br is bonded in a distorted see-saw-like geometry to four Ho atoms. In the second Br site, Br is bonded in a distorted see-saw-like geometry to four Ho atoms. In the third Br site, Br is bonded in a 3-coordinate geometry to three Ho atoms. In the fourth Br site, Br is bonded in a 3-coordinate geometry to three Ho atoms.

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36 MATERIALS SCIENCEBr-Ho-Rucrystal structureHo4RuBr5

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2020-04-29. Materials Data on Ho4RuBr5 by Materials Project. https://doi.org/10.17188/1684155

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