Materials Data on Hf2Al3Cu by Materials Project
Hf2CuAl3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to four equivalent Hf, three equivalent Cu, and nine equivalent Al atoms. There are one shorter (3.10 Å) and three longer (3.22 Å) Hf–Hf bond lengths. All Hf–Cu bond lengths are 3.09 Å. There are three shorter (3.02 Å) and six longer (3.06 Å) Hf–Al bond lengths. Cu is bonded to six equivalent Hf and six equivalent Al atoms to form CuHf6Al6 cuboctahedra that share corners with six equivalent CuHf6Al6 cuboctahedra, corners with twelve equivalent AlHf6Al4Cu2 cuboctahedra, edges with six equivalent CuHf6Al6 cuboctahedra, and faces with eighteen equivalent AlHf6Al4Cu2 cuboctahedra. All Cu–Al bond lengths are 2.57 Å. Al is bonded to six equivalent Hf, two equivalent Cu, and four equivalent Al atoms to form distorted AlHf6Al4Cu2 cuboctahedra that share corners with four equivalent CuHf6Al6 cuboctahedra, corners with fourteen equivalent AlHf6Al4Cu2 cuboctahedra, edges with six equivalent AlHf6Al4Cu2 cuboctahedra, faces with six equivalent CuHf6Al6 cuboctahedra, and faces with twelve equivalent AlHf6Al4Cu2 cuboctahedra. All Al–Al bond lengths are 2.63 Å.