Cu9Sb(AsS6)2 is Stannite-like structured and crystallizes in the tetragonal I-42m space group. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent S(1) atoms to form CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(3)S4 tetrahedra, and corners with four equivalent As(1)S4 tetrahedra. In the second Cu site, Cu(2) is bonded to two equivalent S(2) and two equivalent S(3) atoms to form CuS4 tetrahedra that share corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Sb(1)S4 tetrahedra, corners with two equivalent As(1)S4 tetrahedra, and corners with four equivalent Cu(2)S4 tetrahedra. In the third Cu site, Cu(3) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and corners with four equivalent As(1)S4 tetrahedra. In the fourth Cu site, Cu(4) is bonded to four equivalent S(3) atoms to form CuS4 tetrahedra that share corners with four equivalent Sb(1)S4 tetrahedra and corners with eight equivalent Cu(2)S4 tetrahedra. Sb(1) is bonded to four equivalent S(3) atoms to form SbS4 tetrahedra that share corners with four equivalent Cu(4)S4 tetrahedra and corners with eight equivalent Cu(2)S4 tetrahedra. As(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form AsS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and corners with four equivalent Cu(3)S4 tetrahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Cu(3), two equivalent Cu(1), and one As(1) atom to form corner-sharing SCu3As tetrahedra. In the second S site, S(2) is bonded to one Cu(3), two equivalent Cu(2), and one As(1) atom to form SCu3As tetrahedra that share corners with four equivalent S(1)Cu3As tetrahedra, corners with four equivalent S(2)Cu3As tetrahedra, and corners with four equivalent S(3)Cu3Sb tetrahedra. In the third S site, S(3) is bonded to one Cu(4), two equivalent Cu(2), and one Sb(1) atom to form SCu3Sb tetrahedra that share corners with four equivalent S(2)Cu3As tetrahedra and corners with eight equivalent S(3)Cu3Sb tetrahedra.
Cu9Sb(AsS6)2 is Stannite-like structured and crystallizes in the tetragonal I-42m space group. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent S(1) atoms to form CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(3)S4 tetrahedra, and corners with four equivalent As(1)S4 tetrahedra. All Cu(1)-S(1) bond lengths are 2.30 Å. In the second Cu site, Cu(2) is bonded to two equivalent S(2) and two equivalent S(3) atoms to form CuS4 tetrahedra that share corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Sb(1)S4 tetrahedra, corners with two equivalent As(1)S4 tetrahedra, and corners with four equivalent Cu(2)S4 tetrahedra. Both Cu(2)-S(2) bond lengths are 2.29 Å. Both Cu(2)-S(3) bond lengths are 2.29 Å. In the third Cu site, Cu(3) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and corners with four equivalent As(1)S4 tetrahedra. Both Cu(3)-S(1) bond lengths are 2.33 Å. Both Cu(3)-S(2) bond lengths are 2.31 Å. In the fourth Cu site, Cu(4) is bonded to four equivalent S(3) atoms to form CuS4 tetrahedra that share corners with four equivalent Sb(1)S4 tetrahedra and corners with eight equivalent Cu(2)S4 tetrahedra. All Cu(4)-S(3) bond lengths are 2.30 Å. Sb(1) is bonded to four equivalent S(3) atoms to form SbS4 tetrahedra that share corners with four equivalent Cu(4)S4 tetrahedra and corners with eight equivalent Cu(2)S4 tetrahedra. All Sb(1)-S(3) bond lengths are 2.46 Å. As(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form AsS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and corners with four equivalent Cu(3)S4 tetrahedra. Both As(1)-S(1) bond lengths are 2.31 Å. Both As(1)-S(2) bond lengths are 2.32 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Cu(3), two equivalent Cu(1), and one As(1) atom to form corner-sharing SCu3As tetrahedra. In the second S site, S(2) is bonded to one Cu(3), two equivalent Cu(2), and one As(1) atom to form SCu3As tetrahedra that share corners with four equivalent S(1)Cu3As tetrahedra, corners with four equivalent S(2)Cu3As tetrahedra, and corners with four equivalent S(3)Cu3Sb tetrahedra. In the third S site, S(3) is bonded to one Cu(4), two equivalent Cu(2), and one Sb(1) atom to form SCu3Sb tetrahedra that share corners with four equivalent S(2)Cu3As tetrahedra and corners with eight equivalent S(3)Cu3Sb tetrahedra.