Ta5Al3C crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 2-coordinate geometry to five equivalent Al(1) and two equivalent C(1) atoms. In the second Ta site, Ta(2) is bonded in a 8-coordinate geometry to two equivalent Ta(2) and six equivalent Al(1) atoms. Al(1) is bonded in a 9-coordinate geometry to four equivalent Ta(2) and five equivalent Ta(1) atoms. C(1) is bonded to six equivalent Ta(1) atoms to form face-sharing CTa6 octahedra.
Ta5Al3C crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 2-coordinate geometry to five equivalent Al(1) and two equivalent C(1) atoms. There are a spread of Ta(1)-Al(1) bond distances ranging from 2.76-3.01 Å. Both Ta(1)-C(1) bond lengths are 2.25 Å. In the second Ta site, Ta(2) is bonded in a 8-coordinate geometry to two equivalent Ta(2) and six equivalent Al(1) atoms. Both Ta(2)-Ta(2) bond lengths are 2.68 Å. All Ta(2)-Al(1) bond lengths are 2.72 Å. Al(1) is bonded in a 9-coordinate geometry to four equivalent Ta(2) and five equivalent Ta(1) atoms. C(1) is bonded to six equivalent Ta(1) atoms to form face-sharing CTa6 octahedra.