Materials Data on Hf9Mo4As by Materials Project
Hf9Mo4As crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 2-coordinate geometry to four Mo and one As atom. There are a spread of Hf–Mo bond distances ranging from 2.86–3.12 Å. The Hf–As bond length is 2.74 Å. In the second Hf site, Hf is bonded in a distorted T-shaped geometry to two equivalent Mo and one As atom. Both Hf–Mo bond lengths are 2.92 Å. The Hf–As bond length is 3.10 Å. There are two inequivalent Mo sites. In the first Mo site, Mo is bonded to six equivalent Hf and six equivalent Mo atoms to form face-sharing MoHf6Mo6 cuboctahedra. All Mo–Mo bond lengths are 2.73 Å. In the second Mo site, Mo is bonded in a 12-coordinate geometry to eight Hf and four Mo atoms. Both Mo–Mo bond lengths are 2.87 Å. As is bonded in a 9-coordinate geometry to nine Hf atoms.