Materials Data on YMgAl4 by Materials Project

Abstract

MgYAl4 is Hexagonal Laves-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Mg is bonded in a 12-coordinate geometry to three equivalent Mg, one Y, and twelve Al atoms. All Mg–Mg bond lengths are 3.36 Å. The Mg–Y bond length is 3.31 Å. There are three shorter (3.15 Å) and nine longer (3.23 Å) Mg–Al bond lengths. Y is bonded in a 12-coordinate geometry to one Mg, three equivalent Y, and twelve Al atoms. All Y–Y bond lengths are 3.42 Å. There are a spread of Y–Al bond distances ranging from 3.20–3.27 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded to six equivalent Mg and six equivalent Al atoms to form AlMg6Al6 cuboctahedra that share corners with twelve equivalent AlY3Mg3Al6 cuboctahedra, edges with six equivalent AlMg6Al6 cuboctahedra, and faces with twenty AlY6Al6 cuboctahedra. All Al–Al bond lengths are 2.75 Å. In the second Al site, Al is bonded to six equivalent Y and six equivalent Al atoms to form AlY6Al6 cuboctahedra that share corners with twelve equivalent AlY3Mg3Al6 cuboctahedra, edges with six equivalent AlY6Al6 cuboctahedra, and faces with twenty AlMg6Al6 cuboctahedra. All Al–Al bond lengths are 2.77 Å. In the third Al site, Al is bonded to three equivalent Mg, three equivalent Y, and six Al atoms to form AlY3Mg3Al6 cuboctahedra that share corners with eighteen AlMg6Al6 cuboctahedra, edges with six equivalent AlY3Mg3Al6 cuboctahedra, and faces with eighteen AlMg6Al6 cuboctahedra. There are two shorter (2.70 Å) and two longer (2.82 Å) Al–Al bond lengths.