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DOE OSTI · 1747191

Materials Data on Ho5Mg by Materials Project

Abstract

MgHo5 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Mg is bonded to ten Ho atoms to form distorted MgHo10 cuboctahedra that share corners with four equivalent MgHo10 cuboctahedra, corners with twenty HoHo8Mg4 cuboctahedra, edges with ten HoHo12 cuboctahedra, faces with four equivalent MgHo10 cuboctahedra, and faces with sixteen HoHo12 cuboctahedra. There are a spread of Mg–Ho bond distances ranging from 3.44–3.55 Å. There are five inequivalent Ho sites. In the first Ho site, Ho is bonded to twelve Ho atoms to form HoHo12 cuboctahedra that share corners with eighteen HoHo12 cuboctahedra, edges with eight equivalent MgHo10 cuboctahedra, edges with ten HoHo10Mg2 cuboctahedra, faces with two equivalent MgHo10 cuboctahedra, and faces with eighteen HoHo12 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.44–3.57 Å. In the second Ho site, Ho is bonded to four equivalent Mg and eight Ho atoms to form HoHo8Mg4 cuboctahedra that share corners with four equivalent MgHo10 cuboctahedra, corners with eighteen HoHo12 cuboctahedra, edges with fourteen HoHo12 cuboctahedra, faces with four equivalent MgHo10 cuboctahedra, and faces with sixteen HoHo12 cuboctahedra. There are a spread of Ho–Ho bond distances ranging from 3.44–3.55 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 HoHo12 cuboctahedra, edges with eighteen HoHo12 cuboctahedra, faces with six equivalent MgHo10 cuboctahedra, and faces with fourteen HoHo12 cuboctahedra. There are four shorter (3.45 Å) and two longer (3.55 Å) Ho–Ho bond lengths. In the fourth Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eight equivalent MgHo10 cuboctahedra, corners with twelve HoHo10Mg2 cuboctahedra, an edgeedge with one MgHo10 cuboctahedra, edges with fifteen HoHo12 cuboctahedra, faces with two equivalent MgHo10 cuboctahedra, and faces with eighteen HoHo12 cuboctahedra. There are two shorter (3.52 Å) and two longer (3.55 Å) Ho–Ho bond lengths. In the fifth Ho site, Ho is bonded to two equivalent Mg and ten Ho atoms to form HoHo10Mg2 cuboctahedra that share corners with eight equivalent MgHo10 cuboctahedra, corners with twelve HoHo10Mg2 cuboctahedra, an edgeedge with one MgHo10 cuboctahedra, edges with fifteen HoHo8Mg4 cuboctahedra, faces with two equivalent MgHo10 cuboctahedra, and faces with eighteen HoHo12 cuboctahedra. Both Ho–Ho bond lengths are 3.55 Å.

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2020-05-02. Materials Data on Ho5Mg by Materials Project. https://doi.org/10.17188/1747191

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