Hf5Al3C 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 2-coordinate geometry to five equivalent Al(1) and two equivalent C(1) atoms. In the second Hf site, Hf(2) is bonded in a 8-coordinate geometry to two equivalent Hf(2) and six equivalent Al(1) atoms. Al(1) is bonded in a 9-coordinate geometry to four equivalent Hf(2) and five equivalent Hf(1) atoms. C(1) is bonded to six equivalent Hf(1) atoms to form face-sharing CHf6 octahedra.
Hf5Al3C 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 2-coordinate geometry to five equivalent Al(1) and two equivalent C(1) atoms. There are a spread of Hf(1)-Al(1) bond distances ranging from 2.85-3.20 Å. Both Hf(1)-C(1) bond lengths are 2.32 Å. In the second Hf site, Hf(2) is bonded in a 8-coordinate geometry to two equivalent Hf(2) and six equivalent Al(1) atoms. Both Hf(2)-Hf(2) bond lengths are 2.84 Å. All Hf(2)-Al(1) bond lengths are 2.86 Å. Al(1) is bonded in a 9-coordinate geometry to four equivalent Hf(2) and five equivalent Hf(1) atoms. C(1) is bonded to six equivalent Hf(1) atoms to form face-sharing CHf6 octahedra.