Hf5NiSb3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 8-coordinate geometry to two equivalent Hf(1) and six equivalent Sb(1) atoms. In the second Hf site, Hf(2) is bonded to two equivalent Ni(1) and five equivalent Sb(1) atoms to form a mixture of distorted face, corner, and edge-sharing HfNi2Sb5 pentagonal bipyramids. Ni(1) is bonded to six equivalent Hf(2) atoms to form face-sharing NiHf6 octahedra. Sb(1) is bonded in a 9-coordinate geometry to four equivalent Hf(1) and five equivalent Hf(2) atoms.
Hf5NiSb3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 8-coordinate geometry to two equivalent Hf(1) and six equivalent Sb(1) atoms. Both Hf(1)-Hf(1) bond lengths are 2.85 Å. All Hf(1)-Sb(1) bond lengths are 2.99 Å. In the second Hf site, Hf(2) is bonded to two equivalent Ni(1) and five equivalent Sb(1) atoms to form a mixture of distorted face, corner, and edge-sharing HfNi2Sb5 pentagonal bipyramids. Both Hf(2)-Ni(1) bond lengths are 2.60 Å. There are a spread of Hf(2)-Sb(1) bond distances ranging from 2.92-3.07 Å. Ni(1) is bonded to six equivalent Hf(2) atoms to form face-sharing NiHf6 octahedra. Sb(1) is bonded in a 9-coordinate geometry to four equivalent Hf(1) and five equivalent Hf(2) atoms.