Materials Data on Hf3As2 by Materials Project
Hf3As2 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 5-coordinate geometry to five As atoms. There are a spread of Hf–As bond distances ranging from 2.72–2.80 Å. In the second Hf site, Hf is bonded to five As atoms to form edge-sharing HfAs5 square pyramids. There are a spread of Hf–As bond distances ranging from 2.68–2.73 Å. In the third Hf site, Hf is bonded in a 5-coordinate geometry to five As atoms. There are a spread of Hf–As bond distances ranging from 2.71–3.12 Å. There are two inequivalent As sites. In the first As site, As is bonded to seven Hf atoms to form a mixture of distorted corner and edge-sharing AsHf7 pentagonal bipyramids. In the second As site, As is bonded in a 8-coordinate geometry to eight Hf atoms.