Al(CuS2)3 crystallizes in the tetragonal I-42d space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with two equivalent Cu(1)S4 tetrahedra, corners with two equivalent Cu(2)S4 tetrahedra, and corners with two equivalent Al(1)S4 tetrahedra. In the second Cu site, Cu(2) is bonded to four equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra and corners with four equivalent Al(1)S4 tetrahedra. Al(1) is bonded to four equivalent S(2) atoms to form AlS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra and corners with four equivalent Cu(2)S4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded in a water-like geometry to two equivalent Cu(1) atoms. In the second S site, S(2) is bonded in a trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one Al(1) atom.
Al(CuS2)3 crystallizes in the tetragonal I-42d space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with two equivalent Cu(1)S4 tetrahedra, corners with two equivalent Cu(2)S4 tetrahedra, and corners with two equivalent Al(1)S4 tetrahedra. Both Cu(1)-S(1) bond lengths are 2.16 Å. Both Cu(1)-S(2) bond lengths are 2.26 Å. In the second Cu site, Cu(2) is bonded to four equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra and corners with four equivalent Al(1)S4 tetrahedra. All Cu(2)-S(2) bond lengths are 2.25 Å. Al(1) is bonded to four equivalent S(2) atoms to form AlS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra and corners with four equivalent Cu(2)S4 tetrahedra. All Al(1)-S(2) bond lengths are 2.26 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded in a water-like geometry to two equivalent Cu(1) atoms. In the second S site, S(2) is bonded in a trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one Al(1) atom.