Materials Data on Hf3AlMo8 by Materials Project

Abstract

Hf3Mo8Al is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to four Hf and twelve Mo atoms. There are three shorter (3.27 Å) and one longer (3.29 Å) Hf–Hf bond lengths. There are three shorter (3.12 Å) and nine longer (3.14 Å) Hf–Mo bond lengths. In the second Hf site, Hf is bonded in a 12-coordinate geometry to three equivalent Hf, twelve Mo, and one Al atom. There are nine shorter (3.13 Å) and three longer (3.17 Å) Hf–Mo bond lengths. The Hf–Al bond length is 3.25 Å. In the third Hf site, Hf is bonded in a 12-coordinate geometry to one Hf, twelve Mo, and three equivalent Al atoms. There are three shorter (3.09 Å) and nine longer (3.12 Å) Hf–Mo bond lengths. All Hf–Al bond lengths are 3.26 Å. There are four inequivalent Mo sites. In the first Mo site, Mo is bonded to four Hf, six Mo, and two equivalent Al atoms to form a mixture of edge, face, and corner-sharing MoHf4Al2Mo6 cuboctahedra. There are a spread of Mo–Mo bond distances ranging from 2.66–2.69 Å. Both Mo–Al bond lengths are 3.12 Å. In the second Mo site, Mo is bonded to five Hf, six Mo, and one Al atom to form a mixture of edge, face, and corner-sharing MoHf5AlMo6 cuboctahedra. There are a spread of Mo–Mo bond distances ranging from 2.63–2.68 Å. The Mo–Al bond length is 3.09 Å. In the third Mo site, Mo is bonded to three equivalent Hf, six Mo, and three equivalent Al atoms to form MoHf3Al3Mo6 cuboctahedra that share corners with eighteen MoHf4Al2Mo6 cuboctahedra, edges with six equivalent MoHf3Al3Mo6 cuboctahedra, and faces with eighteen MoHf4Al2Mo6 cuboctahedra. All Mo–Al bond lengths are 3.13 Å. In the fourth Mo site, Mo is bonded to six Hf and six Mo atoms to form MoHf6Mo6 cuboctahedra that share corners with eighteen MoHf4Al2Mo6 cuboctahedra, edges with six equivalent MoHf6Mo6 cuboctahedra, and faces with eighteen MoHf4Al2Mo6 cuboctahedra. Al is bonded in a 12-coordinate geometry to four Hf and twelve Mo atoms.