Materials Data on HfAl2 by Materials Project

Abstract

HfAl2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to four equivalent Hf and twelve Al atoms. There are three shorter (3.23 Å) and one longer (3.25 Å) Hf–Hf bond lengths. There are a spread of Hf–Al bond distances ranging from 3.08–3.11 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six equivalent Hf and six equivalent Al atoms to form a mixture of edge, face, and corner-sharing AlHf6Al6 cuboctahedra. All Al–Al bond lengths are 2.68 Å. In the second Al site, Al is bonded to six equivalent Hf and six Al atoms to form a mixture of edge, face, and corner-sharing AlHf6Al6 cuboctahedra. There are two shorter (2.56 Å) and two longer (2.69 Å) Al–Al bond lengths.