Materials Data on LaAlCu4 by Materials Project

Abstract

LaCu4Al crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. La is bonded in a 6-coordinate geometry to fifteen Cu and three equivalent Al atoms. There are three shorter (3.08 Å) and twelve longer (3.34 Å) La–Cu bond lengths. All La–Al bond lengths are 3.08 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded to three equivalent La, six equivalent Cu, and three equivalent Al atoms to form distorted CuLa3Al3Cu6 cuboctahedra that share corners with twelve equivalent CuLa4Al2Cu6 cuboctahedra, edges with six equivalent CuLa3Al3Cu6 cuboctahedra, and faces with twenty CuLa3Al3Cu6 cuboctahedra. All Cu–Cu bond lengths are 2.53 Å. All Cu–Al bond lengths are 3.08 Å. In the second Cu site, Cu is bonded to four equivalent La, six Cu, and two equivalent Al atoms to form distorted CuLa4Al2Cu6 cuboctahedra that share corners with twenty CuLa3Al3Cu6 cuboctahedra, edges with ten equivalent CuLa4Al2Cu6 cuboctahedra, and faces with sixteen CuLa3Al3Cu6 cuboctahedra. There are two shorter (2.65 Å) and two longer (2.68 Å) Cu–Cu bond lengths. Both Cu–Al bond lengths are 2.54 Å. Al is bonded in a 12-coordinate geometry to three equivalent La and nine Cu atoms.