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DOE OSTI · 1709367

Materials Data on LaYMg6 by Materials Project

Abstract

Mg6LaY is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 11-coordinate geometry to seven Mg, two equivalent La, and two equivalent Y atoms. There are a spread of Mg–Mg bond distances ranging from 3.16–3.41 Å. Both Mg–La bond lengths are 3.33 Å. There are one shorter (3.34 Å) and one longer (3.37 Å) Mg–Y bond lengths. In the second Mg site, Mg is bonded to eight Mg, two equivalent La, and two equivalent Y atoms to form distorted MgLa2Y2Mg8 cuboctahedra that share corners with four equivalent YMg12 cuboctahedra, corners with six equivalent MgLa2Y2Mg8 cuboctahedra, edges with two equivalent YMg12 cuboctahedra, edges with four equivalent LaMg12 cuboctahedra, faces with two equivalent LaMg12 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, and faces with eight MgLa2Y2Mg8 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. Both Mg–La bond lengths are 3.37 Å. Both Mg–Y bond lengths are 3.51 Å. In the third Mg site, Mg is bonded in a 11-coordinate geometry to seven Mg, two equivalent La, and two equivalent Y atoms. There are a spread of Mg–Mg bond distances ranging from 3.21–3.37 Å. There are one shorter (3.35 Å) and one longer (3.36 Å) Mg–La bond lengths. Both Mg–Y bond lengths are 3.31 Å. In the fourth Mg site, Mg is bonded to eight Mg, two equivalent La, and two equivalent Y atoms to form distorted MgLa2Y2Mg8 cuboctahedra that share corners with four equivalent LaMg12 cuboctahedra, corners with six equivalent MgLa2Y2Mg8 cuboctahedra, edges with two equivalent LaMg12 cuboctahedra, edges with four equivalent YMg12 cuboctahedra, faces with two equivalent LaMg12 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, and faces with eight MgLa2Y2Mg8 cuboctahedra. Both Mg–La bond lengths are 3.52 Å. Both Mg–Y bond lengths are 3.32 Å. La is bonded to twelve Mg atoms to form distorted LaMg12 cuboctahedra that share corners with four equivalent MgLa2Y2Mg8 cuboctahedra, corners with six equivalent LaMg12 cuboctahedra, edges with six MgLa2Y2Mg8 cuboctahedra, faces with two equivalent LaMg12 cuboctahedra, faces with four MgLa2Y2Mg8 cuboctahedra, and faces with six equivalent YMg12 cuboctahedra. Y is bonded to twelve Mg atoms to form distorted YMg12 cuboctahedra that share corners with four equivalent MgLa2Y2Mg8 cuboctahedra, corners with six equivalent YMg12 cuboctahedra, edges with six MgLa2Y2Mg8 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, faces with four MgLa2Y2Mg8 cuboctahedra, and faces with six equivalent LaMg12 cuboctahedra.

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2020-05-02. Materials Data on LaYMg6 by Materials Project. https://doi.org/10.17188/1709367

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36 MATERIALS SCIENCE↗