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DOE OSTI · 1739078

Materials Data on CaCeMg6 by Materials Project

Abstract

CaMg6Ce is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ca is bonded to ten Mg and two equivalent Ce atoms to form CaCe2Mg10 cuboctahedra that share corners with six equivalent CaCe2Mg10 cuboctahedra, corners with twelve MgCa2Ce2Mg8 cuboctahedra, edges with four equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. There are a spread of Ca–Mg bond distances ranging from 3.20–3.40 Å. Both Ca–Ce bond lengths are 3.41 Å. There are six inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with four equivalent CeCa2Mg10 cuboctahedra, edges with twelve MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.26–3.41 Å. Both Mg–Ce bond lengths are 3.26 Å. In the second Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with four equivalent CeCa2Mg10 cuboctahedra, edges with twelve MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.26–3.30 Å. Both Mg–Ce bond lengths are 3.26 Å. In the third Mg site, Mg is bonded to two equivalent Ca and ten Mg atoms to form MgCa2Mg10 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with sixteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with six equivalent CeCa2Mg10 cuboctahedra, and faces with twelve MgCa2Ce2Mg8 cuboctahedra. There are four shorter (3.29 Å) and two longer (3.32 Å) Mg–Mg bond lengths. In the fourth Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with four equivalent CeCa2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with four equivalent CaCe2Mg10 cuboctahedra, edges with twelve MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.21–3.40 Å. There are one shorter (3.17 Å) and one longer (3.41 Å) Mg–Ce bond lengths. In the fifth Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with four equivalent CeCa2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with four equivalent CaCe2Mg10 cuboctahedra, edges with twelve MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. There are one shorter (3.21 Å) and one longer (3.36 Å) Mg–Mg bond lengths. There are one shorter (3.17 Å) and one longer (3.41 Å) Mg–Ce bond lengths. In the sixth Mg site, Mg is bonded to ten Mg and two equivalent Ce atoms to form MgCe2Mg10 cuboctahedra that share corners with four equivalent CeCa2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with sixteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, faces with six equivalent CaCe2Mg10 cuboctahedra, and faces with twelve MgCa2Ce2Mg8 cuboctahedra. Both Mg–Ce bond lengths are 3.40 Å. Ce is bonded to two equivalent Ca and ten Mg atoms to form CeCa2Mg10 cuboctahedra that share corners with six equivalent CeCa2Mg10 cuboctahedra, corners with twelve MgCa2Ce2Mg8 cuboctahedra, edges with four equivalent CaCe2Mg10 cuboctahedra, edges with fourteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra.

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2020-05-04. Materials Data on CaCeMg6 by Materials Project. https://doi.org/10.17188/1739078

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