Ta3Al2C crystallizes in the cubic P4_132 space group. Ta(1) is bonded in a bent 150 degrees geometry to six equivalent Al(1) and two equivalent C(1) atoms. Al(1) is bonded to nine equivalent Ta(1) and three equivalent Al(1) atoms to form AlTa9Al3 cuboctahedra that share corners with fifteen equivalent Al(1)Ta9Al3 cuboctahedra, edges with three equivalent C(1)Ta6 octahedra, faces with ten equivalent Al(1)Ta9Al3 cuboctahedra, and faces with four equivalent C(1)Ta6 octahedra. C(1) is bonded to six equivalent Ta(1) atoms to form distorted CTa6 octahedra that share corners with six equivalent C(1)Ta6 octahedra, edges with six equivalent Al(1)Ta9Al3 cuboctahedra, and faces with eight equivalent Al(1)Ta9Al3 cuboctahedra. The corner-sharing octahedral tilt angles are 24°.
Ta3Al2C crystallizes in the cubic P4_132 space group. Ta(1) is bonded in a bent 150 degrees geometry to six equivalent Al(1) and two equivalent C(1) atoms. There are a spread of Ta(1)-Al(1) bond distances ranging from 2.92-3.02 Å. Both Ta(1)-C(1) bond lengths are 2.22 Å. Al(1) is bonded to nine equivalent Ta(1) and three equivalent Al(1) atoms to form AlTa9Al3 cuboctahedra that share corners with fifteen equivalent Al(1)Ta9Al3 cuboctahedra, edges with three equivalent C(1)Ta6 octahedra, faces with ten equivalent Al(1)Ta9Al3 cuboctahedra, and faces with four equivalent C(1)Ta6 octahedra. All Al(1)-Al(1) bond lengths are 2.63 Å. C(1) is bonded to six equivalent Ta(1) atoms to form distorted CTa6 octahedra that share corners with six equivalent C(1)Ta6 octahedra, edges with six equivalent Al(1)Ta9Al3 cuboctahedra, and faces with eight equivalent Al(1)Ta9Al3 cuboctahedra. The corner-sharing octahedral tilt angles are 24°.