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DOE OSTI · 1759536

Materials Data on La5Mg by Materials Project

Abstract

MgLa5 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Mg is bonded to twelve La atoms to form MgLa12 cuboctahedra that share corners with six equivalent MgLa12 cuboctahedra, corners with twelve LaLa9Mg3 cuboctahedra, edges with six equivalent MgLa12 cuboctahedra, edges with twelve LaLa10Mg2 cuboctahedra, and faces with twenty LaLa10Mg2 cuboctahedra. There are six shorter (3.61 Å) and six longer (3.70 Å) Mg–La bond lengths. There are eight inequivalent La sites. In the first La site, La is bonded to two equivalent Mg and ten La atoms to form distorted LaLa10Mg2 cuboctahedra that share corners with eighteen LaLa10Mg2 cuboctahedra, edges with four equivalent MgLa12 cuboctahedra, edges with fourteen LaLa10Mg2 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. There are a spread of La–La bond distances ranging from 3.59–3.80 Å. In the second La site, La is bonded to three equivalent Mg and nine La atoms to form LaLa9Mg3 cuboctahedra that share corners with six equivalent MgLa12 cuboctahedra, corners with twelve LaLa9Mg3 cuboctahedra, edges with eighteen LaLa10Mg2 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. There are three shorter (3.59 Å) and three longer (3.70 Å) La–La bond lengths. In the third La site, La is bonded to three equivalent Mg and nine La atoms to form LaLa9Mg3 cuboctahedra that share corners with six equivalent MgLa12 cuboctahedra, corners with twelve LaLa9Mg3 cuboctahedra, edges with eighteen LaLa10Mg2 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. All La–La bond lengths are 3.68 Å. In the fourth La site, La is bonded to two equivalent Mg and ten La atoms to form distorted LaLa10Mg2 cuboctahedra that share corners with eighteen LaLa10Mg2 cuboctahedra, edges with four equivalent MgLa12 cuboctahedra, edges with fourteen LaLa9Mg3 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. There are four shorter (3.65 Å) and two longer (3.80 Å) La–La bond lengths. In the fifth La site, La is bonded to two equivalent Mg and ten La atoms to form distorted LaLa10Mg2 cuboctahedra that share corners with eighteen LaLa10Mg2 cuboctahedra, edges with four equivalent MgLa12 cuboctahedra, edges with fourteen LaLa9Mg3 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. There are two shorter (3.65 Å) and one longer (3.80 Å) La–La bond lengths. In the sixth La site, La is bonded to two equivalent Mg and ten La atoms to form distorted LaLa10Mg2 cuboctahedra that share corners with eighteen LaLa10Mg2 cuboctahedra, edges with four equivalent MgLa12 cuboctahedra, edges with fourteen LaLa10Mg2 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. In the seventh La site, La is bonded to three equivalent Mg and nine La atoms to form LaLa9Mg3 cuboctahedra that share corners with six equivalent MgLa12 cuboctahedra, corners with twelve LaLa9Mg3 cuboctahedra, edges with eighteen LaLa10Mg2 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. All La–Mg bond lengths are 3.70 Å. There are three shorter (3.68 Å) and three longer (3.70 Å) La–La bond lengths. In the eighth La site, La is bonded to two equivalent Mg and ten La atoms to form distorted LaLa10Mg2 cuboctahedra that share corners with eighteen LaLa10Mg2 cuboctahedra, edges with four equivalent MgLa12 cuboctahedra, edges with fourteen LaLa9Mg3 cuboctahedra, faces with four equivalent MgLa12 cuboctahedra, and faces with sixteen LaLa10Mg2 cuboctahedra. Both La–Mg bond lengths are 3.61 Å. There are a spread of La–La bond distances ranging from 3.59–3.80 Å.

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2020-09-03. Materials Data on La5Mg by Materials Project. https://doi.org/10.17188/1759536

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