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DOE OSTI · 1692530

Materials Data on ErMg5 by Materials Project

Abstract

Mg5Er crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded in a 11-coordinate geometry to nine Mg and two equivalent Er atoms. There are a spread of Mg–Mg bond distances ranging from 3.15–3.25 Å. Both Mg–Er bond lengths are 3.27 Å. In the second Mg site, Mg is bonded in a 11-coordinate geometry to nine Mg and two equivalent Er atoms. There are a spread of Mg–Mg bond distances ranging from 3.15–3.28 Å. Both Mg–Er bond lengths are 3.25 Å. In the third Mg site, Mg is bonded to eleven Mg and one Er atom to form distorted MgErMg11 cuboctahedra that share corners with twelve MgErMg11 cuboctahedra, edges with four equivalent ErEr2Mg10 cuboctahedra, edges with five MgEr2Mg10 cuboctahedra, faces with four equivalent ErEr2Mg10 cuboctahedra, and faces with ten MgErMg11 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.25–3.41 Å. The Mg–Er bond length is 3.31 Å. In the fourth Mg site, Mg is bonded to ten Mg and two equivalent Er atoms to form MgEr2Mg10 cuboctahedra that share corners with six equivalent MgEr2Mg10 cuboctahedra, corners with six equivalent ErEr2Mg10 cuboctahedra, edges with three equivalent ErEr2Mg10 cuboctahedra, edges with eight MgErMg11 cuboctahedra, faces with three equivalent ErEr2Mg10 cuboctahedra, and faces with ten MgErMg11 cuboctahedra. There are two shorter (3.18 Å) and two longer (3.25 Å) Mg–Mg bond lengths. Both Mg–Er bond lengths are 3.33 Å. In the fifth Mg site, Mg is bonded to nine Mg and three equivalent Er atoms to form MgEr3Mg9 cuboctahedra that share corners with twelve MgErMg11 cuboctahedra, edges with two equivalent ErEr2Mg10 cuboctahedra, edges with nine MgErMg11 cuboctahedra, faces with five equivalent ErEr2Mg10 cuboctahedra, and faces with eight MgErMg11 cuboctahedra. Both Mg–Mg bond lengths are 3.25 Å. There are two shorter (3.35 Å) and one longer (3.40 Å) Mg–Er bond lengths. Er is bonded to ten Mg and two equivalent Er atoms to form ErEr2Mg10 cuboctahedra that share corners with six equivalent MgEr2Mg10 cuboctahedra, corners with six equivalent ErEr2Mg10 cuboctahedra, edges with nine MgErMg11 cuboctahedra, faces with two equivalent ErEr2Mg10 cuboctahedra, and faces with twelve MgErMg11 cuboctahedra. Both Er–Er bond lengths are 3.25 Å.

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2020-05-03. Materials Data on ErMg5 by Materials Project. https://doi.org/10.17188/1692530

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