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DOE OSTI · 1717291

Materials Data on CeMg by Materials Project

Abstract

CeMg crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to seven Mg and five Ce atoms to form MgCe5Mg7 cuboctahedra that share corners with six equivalent CeCe7Mg5 cuboctahedra, corners with twelve MgCe5Mg7 cuboctahedra, edges with five MgCe6Mg6 cuboctahedra, edges with thirteen CeCe7Mg5 cuboctahedra, faces with ten MgCe5Mg7 cuboctahedra, and faces with ten CeCe7Mg5 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.14–3.42 Å. There are a spread of Mg–Ce bond distances ranging from 3.52–3.57 Å. In the second Mg site, Mg is bonded to six Mg and six Ce atoms to form MgCe6Mg6 cuboctahedra that share corners with six equivalent CeCe7Mg5 cuboctahedra, corners with twelve MgCe5Mg7 cuboctahedra, edges with nine MgCe5Mg7 cuboctahedra, edges with nine CeCe7Mg5 cuboctahedra, faces with eight MgCe5Mg7 cuboctahedra, and faces with twelve CeCe7Mg5 cuboctahedra. There are two shorter (3.13 Å) and two longer (3.14 Å) Mg–Mg bond lengths. There are a spread of Mg–Ce bond distances ranging from 3.30–3.46 Å. In the third Mg site, Mg is bonded to seven Mg and five Ce atoms to form distorted MgCe5Mg7 cuboctahedra that share corners with six equivalent MgCe5Mg7 cuboctahedra, corners with twelve CeCe7Mg5 cuboctahedra, edges with eight MgCe5Mg7 cuboctahedra, edges with ten CeCe7Mg5 cuboctahedra, faces with ten MgCe5Mg7 cuboctahedra, and faces with ten CeCe7Mg5 cuboctahedra. Both Mg–Mg bond lengths are 3.14 Å. There are a spread of Mg–Ce bond distances ranging from 3.39–3.59 Å. There are three inequivalent Ce sites. In the first Ce site, Ce is bonded to five Mg and seven Ce atoms to form distorted CeCe7Mg5 cuboctahedra that share corners with six equivalent MgCe5Mg7 cuboctahedra, corners with twelve CeCe7Mg5 cuboctahedra, edges with five CeCe7Mg5 cuboctahedra, edges with thirteen MgCe5Mg7 cuboctahedra, faces with ten MgCe5Mg7 cuboctahedra, and faces with ten CeCe7Mg5 cuboctahedra. There are a spread of Ce–Ce bond distances ranging from 3.08–3.65 Å. In the second Ce site, Ce is bonded to five Mg and seven Ce atoms to form distorted CeCe7Mg5 cuboctahedra that share corners with six equivalent CeCe7Mg5 cuboctahedra, corners with twelve MgCe5Mg7 cuboctahedra, edges with eight CeCe7Mg5 cuboctahedra, edges with ten MgCe5Mg7 cuboctahedra, faces with ten MgCe5Mg7 cuboctahedra, and faces with ten CeCe7Mg5 cuboctahedra. There are two shorter (3.09 Å) and two longer (3.14 Å) Ce–Ce bond lengths. In the third Ce site, Ce is bonded to six Mg and six Ce atoms to form CeCe6Mg6 cuboctahedra that share corners with six equivalent MgCe5Mg7 cuboctahedra, corners with twelve CeCe7Mg5 cuboctahedra, edges with nine MgCe5Mg7 cuboctahedra, edges with nine CeCe7Mg5 cuboctahedra, faces with eight CeCe7Mg5 cuboctahedra, and faces with twelve MgCe5Mg7 cuboctahedra. Both Ce–Ce bond lengths are 3.14 Å.

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2020-05-03. Materials Data on CeMg by Materials Project. https://doi.org/10.17188/1717291

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