Materials Data on Hf5Ge4 by Materials Project
Hf5Ge4 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 to seven Ge atoms to form distorted HfGe7 pentagonal bipyramids that share corners with four equivalent HfGe6 octahedra, corners with six equivalent HfGe7 pentagonal bipyramids, edges with two equivalent HfGe7 pentagonal bipyramids, faces with two equivalent HfGe6 octahedra, and faces with three equivalent HfGe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–52°. There are a spread of Hf–Ge bond distances ranging from 2.79–3.15 Å. In the second Hf site, Hf is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.66–2.82 Å. In the third Hf site, Hf is bonded to six Ge atoms to form distorted HfGe6 octahedra that share corners with four equivalent HfGe6 octahedra, corners with eight equivalent HfGe7 pentagonal bipyramids, and faces with four equivalent HfGe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–55°. There are a spread of Hf–Ge bond distances ranging from 2.69–2.93 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to eight Hf and one Ge atom. The Ge–Ge bond length is 2.65 Å. In the second Ge site, Ge is bonded in a 8-coordinate geometry to eight Hf atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to eight Hf and one Ge atom.