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DOE OSTI · 1685093

Materials Data on Ca3Mg by Materials Project

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Abstract

MgCa3 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to twelve Ca atoms to form a mixture of corner, edge, and face-sharing CaCa12 cuboctahedra. There are six shorter (3.82 Å) and six longer (3.92 Å) Ca–Ca bond lengths. In the second Ca site, Ca is bonded to three equivalent Ca and three equivalent Mg atoms to form distorted CaCa3Mg3 cuboctahedra that share corners with eighteen CaCa12 cuboctahedra, edges with twelve CaCa12 cuboctahedra, and faces with two equivalent CaCa3Mg3 cuboctahedra. All Ca–Mg bond lengths are 3.52 Å. Mg is bonded in a 6-coordinate geometry to six equivalent Ca atoms.

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36 MATERIALS SCIENCECa-MgCa3Mgcrystal structure

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2020-05-03. Materials Data on Ca3Mg by Materials Project. https://doi.org/10.17188/1685093

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