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DOE OSTI · 1750203

Materials Data on NaCeMg6 by Materials Project

Abstract

NaMg6Ce is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Na is bonded to ten Mg and two equivalent Ce atoms to form NaCe2Mg10 cuboctahedra that share corners with six equivalent NaCe2Mg10 cuboctahedra, corners with twelve MgNa2Mg10 cuboctahedra, edges with four equivalent CeNa2Mg10 cuboctahedra, edges with fourteen MgNa2Mg10 cuboctahedra, faces with two equivalent NaCe2Mg10 cuboctahedra, faces with two equivalent CeNa2Mg10 cuboctahedra, and faces with sixteen MgNa2Ce2Mg8 cuboctahedra. There are a spread of Na–Mg bond distances ranging from 3.27–3.43 Å. Both Na–Ce bond lengths are 3.33 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent Ce atoms to form distorted MgNa2Ce2Mg8 cuboctahedra that share corners with four equivalent CeNa2Mg10 cuboctahedra, corners with fourteen MgNa2Ce2Mg8 cuboctahedra, edges with two equivalent CeNa2Mg10 cuboctahedra, edges with four equivalent NaCe2Mg10 cuboctahedra, edges with twelve MgNa2Ce2Mg8 cuboctahedra, faces with two equivalent NaCe2Mg10 cuboctahedra, faces with two equivalent CeNa2Mg10 cuboctahedra, and faces with sixteen MgNa2Ce2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.26–3.42 Å. There are one shorter (3.33 Å) and one longer (3.42 Å) Mg–Ce bond lengths. In the second Mg site, Mg is bonded to ten Mg and two equivalent Ce atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent CeNa2Mg10 cuboctahedra, corners with fourteen MgNa2Ce2Mg8 cuboctahedra, edges with two equivalent CeNa2Mg10 cuboctahedra, edges with sixteen MgNa2Mg10 cuboctahedra, faces with two equivalent CeNa2Mg10 cuboctahedra, faces with six equivalent NaCe2Mg10 cuboctahedra, and faces with twelve MgNa2Ce2Mg8 cuboctahedra. There are four shorter (3.27 Å) and two longer (3.30 Å) Mg–Mg bond lengths. Both Mg–Ce bond lengths are 3.37 Å. In the third Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent Ce atoms to form distorted MgNa2Ce2Mg8 cuboctahedra that share corners with four equivalent NaCe2Mg10 cuboctahedra, corners with fourteen MgNa2Mg10 cuboctahedra, edges with two equivalent NaCe2Mg10 cuboctahedra, edges with four equivalent CeNa2Mg10 cuboctahedra, edges with twelve MgNa2Ce2Mg8 cuboctahedra, faces with two equivalent NaCe2Mg10 cuboctahedra, faces with two equivalent CeNa2Mg10 cuboctahedra, and faces with sixteen MgNa2Ce2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.34–3.39 Å. Both Mg–Ce bond lengths are 3.28 Å. In the fourth Mg site, Mg is bonded to two equivalent Na and ten Mg atoms to form distorted MgNa2Mg10 cuboctahedra that share corners with four equivalent NaCe2Mg10 cuboctahedra, corners with fourteen MgNa2Mg10 cuboctahedra, edges with two equivalent NaCe2Mg10 cuboctahedra, edges with sixteen MgNa2Ce2Mg8 cuboctahedra, faces with two equivalent NaCe2Mg10 cuboctahedra, faces with six equivalent CeNa2Mg10 cuboctahedra, and faces with twelve MgNa2Ce2Mg8 cuboctahedra. Ce is bonded to two equivalent Na and ten Mg atoms to form CeNa2Mg10 cuboctahedra that share corners with six equivalent CeNa2Mg10 cuboctahedra, corners with twelve MgNa2Ce2Mg8 cuboctahedra, edges with four equivalent NaCe2Mg10 cuboctahedra, edges with fourteen MgNa2Ce2Mg8 cuboctahedra, faces with two equivalent NaCe2Mg10 cuboctahedra, faces with two equivalent CeNa2Mg10 cuboctahedra, and faces with sixteen MgNa2Ce2Mg8 cuboctahedra.

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2020-05-03. Materials Data on NaCeMg6 by Materials Project. https://doi.org/10.17188/1750203

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