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DOE OSTI · 1757348

Materials Data on MgZn5 by Materials Project

Abstract

MgZn5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Mg is bonded to two equivalent Mg and ten Zn atoms to form distorted MgMg2Zn10 cuboctahedra that share corners with six equivalent MgMg2Zn10 cuboctahedra, corners with twelve ZnMg2Zn10 cuboctahedra, edges with eighteen ZnMg2Zn10 cuboctahedra, faces with two equivalent MgMg2Zn10 cuboctahedra, and faces with eighteen ZnMg2Zn10 cuboctahedra. Both Mg–Mg bond lengths are 2.87 Å. There are a spread of Mg–Zn bond distances ranging from 2.80–2.88 Å. There are five inequivalent Zn sites. In the first Zn site, Zn is bonded to two equivalent Mg and ten Zn atoms to form distorted ZnMg2Zn10 cuboctahedra that share corners with eighteen ZnMg2Zn10 cuboctahedra, edges with six equivalent MgMg2Zn10 cuboctahedra, edges with twelve ZnMg3Zn9 cuboctahedra, faces with three equivalent MgMg2Zn10 cuboctahedra, and faces with seventeen ZnMg2Zn10 cuboctahedra. There are a spread of Zn–Zn bond distances ranging from 2.69–2.90 Å. In the second Zn site, Zn is bonded to three equivalent Mg and nine Zn atoms to form distorted ZnMg3Zn9 cuboctahedra that share corners with eighteen ZnMg2Zn10 cuboctahedra, edges with two equivalent MgMg2Zn10 cuboctahedra, edges with sixteen ZnMg2Zn10 cuboctahedra, faces with five equivalent MgMg2Zn10 cuboctahedra, and faces with fifteen ZnMg2Zn10 cuboctahedra. There are a spread of Zn–Zn bond distances ranging from 2.80–2.87 Å. In the third Zn site, Zn is bonded to two equivalent Mg and ten Zn atoms to form ZnMg2Zn10 cuboctahedra that share corners with six equivalent MgMg2Zn10 cuboctahedra, corners with twelve ZnMg2Zn10 cuboctahedra, edges with three equivalent MgMg2Zn10 cuboctahedra, edges with fifteen ZnMg2Zn10 cuboctahedra, faces with three equivalent MgMg2Zn10 cuboctahedra, and faces with seventeen ZnMg2Zn10 cuboctahedra. There are a spread of Zn–Zn bond distances ranging from 2.74–2.87 Å. In the fourth Zn site, Zn is bonded to one Mg and eleven Zn atoms to form distorted ZnMgZn11 cuboctahedra that share corners with eighteen ZnMg2Zn10 cuboctahedra, edges with four equivalent MgMg2Zn10 cuboctahedra, edges with fourteen ZnMg2Zn10 cuboctahedra, faces with four equivalent MgMg2Zn10 cuboctahedra, and faces with sixteen ZnMg2Zn10 cuboctahedra. There are two shorter (2.79 Å) and two longer (2.87 Å) Zn–Zn bond lengths. In the fifth Zn site, Zn is bonded to two equivalent Mg and ten Zn atoms to form distorted ZnMg2Zn10 cuboctahedra that share corners with six equivalent MgMg2Zn10 cuboctahedra, corners with twelve ZnMg2Zn10 cuboctahedra, edges with three equivalent MgMg2Zn10 cuboctahedra, edges with fifteen ZnMg2Zn10 cuboctahedra, faces with three equivalent MgMg2Zn10 cuboctahedra, and faces with seventeen ZnMg2Zn10 cuboctahedra. Both Zn–Zn bond lengths are 2.87 Å.

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2020-09-03. Materials Data on MgZn5 by Materials Project. https://doi.org/10.17188/1757348

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