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DOE OSTI · 1652992

Materials Data on NaMg14Al by Materials Project

Abstract

NaMg14Al crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Na is bonded to ten Mg and two equivalent Al atoms to form NaMg10Al2 cuboctahedra that share corners with six equivalent NaMg10Al2 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with two equivalent AlNa2Mg10 cuboctahedra, edges with sixteen MgNa2Mg8Al2 cuboctahedra, faces with two equivalent AlNa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Na–Mg bond distances ranging from 3.16–3.22 Å. Both Na–Al bond lengths are 3.19 Å. There are ten inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent NaMg10Al2 cuboctahedra, corners with fourteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent AlNa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.18–3.21 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent AlNa2Mg10 cuboctahedra, corners with fourteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent NaMg10Al2 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.21 Å. In the third Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent Al atoms to form distorted MgNa2Mg8Al2 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with two equivalent NaMg10Al2 cuboctahedra, edges with two equivalent AlNa2Mg10 cuboctahedra, edges with fourteen MgNa2Mg8Al2 cuboctahedra, faces with two equivalent NaMg10Al2 cuboctahedra, faces with two equivalent AlNa2Mg10 cuboctahedra, and faces with sixteen MgNa2Mg8Al2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.15–3.24 Å. There are one shorter (3.15 Å) and one longer (3.21 Å) Mg–Al bond lengths. In the fourth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent NaMg10Al2 cuboctahedra, corners with four equivalent AlNa2Mg10 cuboctahedra, corners with ten MgNa2Mg8Al2 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.16–3.23 Å. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent NaMg10Al2 cuboctahedra, corners with four equivalent AlNa2Mg10 cuboctahedra, corners with ten MgNa2Mg8Al2 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.16–3.23 Å. In the sixth Mg site, Mg is bonded to one Na, ten Mg, and one Al atom to form distorted MgNaMg10Al cuboctahedra that share corners with eighteen MgNaMg10Al cuboctahedra, edges with two equivalent NaMg10Al2 cuboctahedra, edges with two equivalent AlNa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one NaMg10Al2 cuboctahedra, a faceface with one AlNa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.13–3.25 Å. The Mg–Al bond length is 3.16 Å. In the seventh Mg site, Mg is bonded to one Na, ten Mg, and one Al atom to form distorted MgNaMg10Al cuboctahedra that share corners with eighteen MgNaMg10Al cuboctahedra, edges with two equivalent NaMg10Al2 cuboctahedra, edges with two equivalent AlNa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one NaMg10Al2 cuboctahedra, a faceface with one AlNa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.13–3.25 Å. The Mg–Al bond length is 3.16 Å. In the eighth Mg site, Mg is bonded to eleven Mg and one Al atom to form distorted MgMg11Al cuboctahedra that share corners with eighteen MgNaMg10Al cuboctahedra, edges with two equivalent AlNa2Mg10 cuboctahedra, edges with sixteen MgMg12 cuboctahedra, a faceface with one AlNa2Mg10 cuboctahedra, faces with three equivalent NaMg10Al2 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are two shorter (3.19 Å) and one longer (3.23 Å) Mg–Mg bond lengths. The Mg–Al bond length is 3.16 Å. In the ninth Mg site, Mg is bonded to one Na and eleven Mg atoms to form distorted MgNaMg11 cuboctahedra that share corners with eighteen MgNaMg10Al cuboctahedra, edges with two equivalent NaMg10Al2 cuboctahedra, edges with sixteen MgMg12 cuboctahedra, a faceface with one NaMg10Al2 cuboctahedra, faces with three equivalent AlNa2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. The Mg–Mg bond length is 3.16 Å. In the tenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent NaMg10Al2 cuboctahedra, corners with four equivalent AlNa2Mg10 cuboctahedra, corners with ten MgNa2Mg8Al2 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.19 Å. Al is bonded to two equivalent Na and ten Mg atoms to form AlNa2Mg10 cuboctahedra that share corners with six equivalent AlNa2Mg10 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with two equivalent NaMg10Al2 cuboctahedra, edges with sixteen MgNa2Mg8Al2 cuboctahedra, faces with two equivalent NaMg10Al2 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra.

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2019-10-23. Materials Data on NaMg14Al by Materials Project. https://doi.org/10.17188/1652992

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