Materials Data on YbAlCu4 by Materials Project

Abstract

YbCu4Al crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Yb is bonded in a 6-coordinate geometry to fifteen Cu and three equivalent Al atoms. There are three shorter (2.97 Å) and twelve longer (3.27 Å) Yb–Cu bond lengths. All Yb–Al bond lengths are 2.97 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded to three equivalent Yb, six equivalent Cu, and three equivalent Al atoms to form CuYb3Al3Cu6 cuboctahedra that share corners with nine equivalent AlYb3Cu9 cuboctahedra, corners with twelve equivalent CuYb4Al2Cu6 cuboctahedra, edges with six equivalent CuYb3Al3Cu6 cuboctahedra, faces with three equivalent AlYb3Cu9 cuboctahedra, and faces with twenty CuYb3Al3Cu6 cuboctahedra. All Cu–Cu bond lengths are 2.50 Å. All Cu–Al bond lengths are 2.97 Å. In the second Cu site, Cu is bonded to four equivalent Yb, six Cu, and two equivalent Al atoms to form distorted CuYb4Al2Cu6 cuboctahedra that share corners with four equivalent AlYb3Cu9 cuboctahedra, corners with twenty CuYb3Al3Cu6 cuboctahedra, edges with ten equivalent CuYb4Al2Cu6 cuboctahedra, faces with six equivalent AlYb3Cu9 cuboctahedra, and faces with sixteen CuYb3Al3Cu6 cuboctahedra. There are two shorter (2.56 Å) and two longer (2.59 Å) Cu–Cu bond lengths. Both Cu–Al bond lengths are 2.51 Å. Al is bonded to three equivalent Yb and nine Cu atoms to form distorted AlYb3Cu9 cuboctahedra that share corners with twenty-one CuYb3Al3Cu6 cuboctahedra, edges with six equivalent AlYb3Cu9 cuboctahedra, faces with two equivalent AlYb3Cu9 cuboctahedra, and faces with twenty-one CuYb3Al3Cu6 cuboctahedra.