Materials Data on HfAlPd by Materials Project

Abstract

HfPdAl crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to three equivalent Hf, five Pd, and seven Al atoms. There are one shorter (3.20 Å) and two longer (3.24 Å) Hf–Hf bond lengths. There are a spread of Hf–Pd bond distances ranging from 2.95–3.15 Å. There are a spread of Hf–Al bond distances ranging from 3.10–3.14 Å. In the second Hf site, Hf is bonded in a 12-coordinate geometry to four Hf, seven Pd, and five Al atoms. The Hf–Hf bond length is 3.07 Å. There are two shorter (3.04 Å) and five longer (3.08 Å) Hf–Pd bond lengths. There are a spread of Hf–Al bond distances ranging from 3.04–3.13 Å. There are three inequivalent Pd sites. In the first Pd site, Pd is bonded to six Hf and six Al atoms to form distorted PdHf6Al6 cuboctahedra that share corners with four equivalent AlHf6Al2Pd4 cuboctahedra, corners with fourteen PdHf6Al6 cuboctahedra, edges with six PdHf6Al6 cuboctahedra, faces with four equivalent PdHf6Al2Pd4 cuboctahedra, and faces with six equivalent AlHf6Al2Pd4 cuboctahedra. There are a spread of Pd–Al bond distances ranging from 2.58–2.71 Å. In the second Pd site, Pd is bonded to six Hf, four Pd, and two equivalent Al atoms to form distorted PdHf6Al2Pd4 cuboctahedra that share corners with four equivalent AlHf6Al2Pd4 cuboctahedra, corners with eight PdHf6Al6 cuboctahedra, edges with two equivalent PdHf6Al2Pd4 cuboctahedra, faces with six equivalent AlHf6Al2Pd4 cuboctahedra, and faces with ten PdHf6Al6 cuboctahedra. There are a spread of Pd–Pd bond distances ranging from 2.62–2.71 Å. Both Pd–Al bond lengths are 2.58 Å. In the third Pd site, Pd is bonded to six Hf, four equivalent Pd, and two equivalent Al atoms to form distorted PdHf6Al2Pd4 cuboctahedra that share corners with four equivalent AlHf6Al2Pd4 cuboctahedra, corners with six PdHf6Al6 cuboctahedra, edges with six PdHf6Al6 cuboctahedra, faces with six equivalent AlHf6Al2Pd4 cuboctahedra, and faces with eight equivalent PdHf6Al2Pd4 cuboctahedra. Both Pd–Al bond lengths are 2.59 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six Hf, four Pd, and two equivalent Al atoms to form distorted AlHf6Al2Pd4 cuboctahedra that share corners with eight PdHf6Al6 cuboctahedra, edges with six equivalent AlHf6Al2Pd4 cuboctahedra, faces with two equivalent AlHf6Al2Pd4 cuboctahedra, and faces with twelve PdHf6Al6 cuboctahedra. Both Al–Al bond lengths are 2.68 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to six Hf, two equivalent Pd, and four Al atoms. There are one shorter (2.58 Å) and one longer (2.77 Å) Al–Al bond lengths.