Materials Data on Hf9AsW4 by Materials Project
Hf9W4As 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 W and one As atom. There are a spread of Hf–W bond distances ranging from 2.88–3.11 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 W and one As atom. Both Hf–W bond lengths are 2.92 Å. The Hf–As bond length is 3.12 Å. There are two inequivalent W sites. In the first W site, W is bonded to six equivalent Hf and six equivalent W atoms to form face-sharing WHf6W6 cuboctahedra. All W–W bond lengths are 2.74 Å. In the second W site, W is bonded in a 12-coordinate geometry to eight Hf and four W atoms. Both W–W bond lengths are 2.87 Å. As is bonded in a 9-coordinate geometry to nine Hf atoms.