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DOE OSTI · 1724785

Materials Data on Ho5Mg by Materials Project

Abstract

MgHo5 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Mg is bonded to twelve Ho atoms to form MgHo12 cuboctahedra that share corners with six equivalent MgHo12 cuboctahedra, corners with twelve equivalent HoHo9Mg3 cuboctahedra, edges with six equivalent MgHo12 cuboctahedra, edges with twelve HoHo10Mg2 cuboctahedra, and faces with twenty HoHo10Mg2 cuboctahedra. There are six shorter (3.43 Å) and six longer (3.53 Å) Mg–Ho bond lengths. There are eight inequivalent Ho sites. In the first Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eighteen HoHo10Mg2 cuboctahedra, edges with four equivalent MgHo12 cuboctahedra, edges with fourteen HoHo10Mg2 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.41–3.57 Å. In the second Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eighteen HoHo10Mg2 cuboctahedra, edges with four equivalent MgHo12 cuboctahedra, edges with fourteen HoHo10Mg2 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.41–3.57 Å. In the third Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eighteen HoHo10Mg2 cuboctahedra, edges with four equivalent MgHo12 cuboctahedra, edges with fourteen HoHo9Mg3 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.41–3.57 Å. In the fourth Ho site, Ho is bonded to three equivalent Mg and nine Ho atoms to form HoHo9Mg3 cuboctahedra that share corners with six equivalent MgHo12 cuboctahedra, corners with twelve HoHo9Mg3 cuboctahedra, edges with eighteen HoHo10Mg2 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.41–3.53 Å. In the fifth Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eighteen HoHo10Mg2 cuboctahedra, edges with four equivalent MgHo12 cuboctahedra, edges with fourteen HoHo9Mg3 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. The Ho–Ho bond length is 3.41 Å. In the sixth Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eighteen HoHo10Mg2 cuboctahedra, edges with four equivalent MgHo12 cuboctahedra, edges with fourteen HoHo9Mg3 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.47–3.57 Å. In the seventh Ho site, Ho is bonded to three equivalent Mg and nine Ho atoms to form HoHo9Mg3 cuboctahedra that share corners with six equivalent MgHo12 cuboctahedra, corners with twelve equivalent HoHo9Mg3 cuboctahedra, edges with eighteen HoHo10Mg2 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. All Ho–Mg bond lengths are 3.53 Å. There are one shorter (3.47 Å) and three longer (3.53 Å) Ho–Ho bond lengths. In the eighth Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eighteen HoHo10Mg2 cuboctahedra, edges with four equivalent MgHo12 cuboctahedra, edges with fourteen HoHo9Mg3 cuboctahedra, faces with four equivalent MgHo12 cuboctahedra, and faces with sixteen HoHo10Mg2 cuboctahedra. Both Ho–Mg bond lengths are 3.43 Å. There are two shorter (3.41 Å) and one longer (3.47 Å) Ho–Ho bond lengths.

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2020-05-03. Materials Data on Ho5Mg by Materials Project. https://doi.org/10.17188/1724785

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