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DOE OSTI · 1751170

Materials Data on Er5Mg by Materials Project

Abstract

MgEr5 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Mg is bonded to twelve Er atoms to form MgEr12 cuboctahedra that share corners with six equivalent MgEr12 cuboctahedra, corners with twelve ErEr9Mg3 cuboctahedra, edges with six equivalent MgEr12 cuboctahedra, edges with twelve ErEr10Mg2 cuboctahedra, and faces with twenty ErEr10Mg2 cuboctahedra. There are six shorter (3.41 Å) and six longer (3.51 Å) Mg–Er bond lengths. There are eleven inequivalent Er sites. In the first Er site, Er is bonded to two equivalent Mg and ten Er atoms to form ErEr10Mg2 cuboctahedra that share corners with eighteen ErEr10Mg2 cuboctahedra, edges with four equivalent MgEr12 cuboctahedra, edges with fourteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. There are a spread of Er–Er bond distances ranging from 3.40–3.55 Å. In the second Er site, Er is bonded to two equivalent Mg and ten Er atoms to form ErEr10Mg2 cuboctahedra that share corners with eighteen ErEr10Mg2 cuboctahedra, edges with four equivalent MgEr12 cuboctahedra, edges with fourteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. There are two shorter (3.40 Å) and two longer (3.45 Å) Er–Er bond lengths. In the third Er site, Er is bonded to three equivalent Mg and nine Er atoms to form ErEr9Mg3 cuboctahedra that share corners with six equivalent MgEr12 cuboctahedra, corners with twelve ErEr9Mg3 cuboctahedra, edges with eighteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. There are two shorter (3.45 Å) and three longer (3.51 Å) Er–Er bond lengths. In the fourth Er site, Er is bonded to three equivalent Mg and nine Er atoms to form ErEr9Mg3 cuboctahedra that share corners with six equivalent MgEr12 cuboctahedra, corners with twelve ErEr9Mg3 cuboctahedra, edges with eighteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. Both Er–Er bond lengths are 3.40 Å. In the fifth Er site, Er is bonded to two equivalent Mg and ten Er atoms to form ErEr10Mg2 cuboctahedra that share corners with eighteen ErEr10Mg2 cuboctahedra, edges with four equivalent MgEr12 cuboctahedra, edges with fourteen ErEr9Mg3 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. There are a spread of Er–Er bond distances ranging from 3.40–3.55 Å. In the sixth Er site, Er is bonded to two equivalent Mg and ten Er atoms to form ErEr10Mg2 cuboctahedra that share corners with eighteen ErEr10Mg2 cuboctahedra, edges with four equivalent MgEr12 cuboctahedra, edges with fourteen ErEr9Mg3 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. There are a spread of Er–Er bond distances ranging from 3.40–3.55 Å. In the seventh Er site, Er is bonded to two equivalent Mg and ten Er atoms to form ErEr10Mg2 cuboctahedra that share corners with eighteen ErEr10Mg2 cuboctahedra, edges with four equivalent MgEr12 cuboctahedra, edges with fourteen ErEr9Mg3 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. Both Er–Mg bond lengths are 3.41 Å. There are a spread of Er–Er bond distances ranging from 3.40–3.55 Å. In the eighth Er site, Er is bonded to three equivalent Mg and nine Er atoms to form ErEr9Mg3 cuboctahedra that share corners with six equivalent MgEr12 cuboctahedra, corners with twelve ErEr9Mg3 cuboctahedra, edges with eighteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. All Er–Mg bond lengths are 3.51 Å. There are a spread of Er–Er bond distances ranging from 3.40–3.51 Å. In the ninth Er site, Er is bonded to three equivalent Mg and nine Er atoms to form ErEr9Mg3 cuboctahedra that share corners with six equivalent MgEr12 cuboctahedra, corners with twelve ErEr9Mg3 cuboctahedra, edges with eighteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. All Er–Mg bond lengths are 3.51 Å. There are two shorter (3.40 Å) and one longer (3.45 Å) Er–Er bond lengths. In the tenth Er site, Er is bonded to two equivalent Mg and ten Er atoms to form ErEr10Mg2 cuboctahedra that share corners with eighteen ErEr10Mg2 cuboctahedra, edges with four equivalent MgEr12 cuboctahedra, edges with fourteen ErEr9Mg3 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. Both Er–Mg bond lengths are 3.41 Å. There are a spread of Er–Er bond distances ranging from 3.40–3.55 Å. In the eleventh Er site, Er is bonded to three equivalent Mg and nine Er atoms to form ErEr9Mg3 cuboctahedra that share corners with six equivalent MgEr12 cuboctahedra, corners with twelve ErEr9Mg3 cuboctahedra, edges with eighteen ErEr10Mg2 cuboctahedra, faces with four equivalent MgEr12 cuboctahedra, and faces with sixteen ErEr10Mg2 cuboctahedra. All Er–Mg bond lengths are 3.51 Å. All Er–Er bond lengths are 3.51 Å.

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2020-05-03. Materials Data on Er5Mg by Materials Project. https://doi.org/10.17188/1751170

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