Ga7(CuSe4)3 crystallizes in the monoclinic Cm space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(7), one Se(8), and two equivalent Se(10) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(3)Se4 tetrahedra,  a cornercorner with one Ga(4)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, corners with two equivalent Ga(6)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(11), one Se(5), and two equivalent Se(12) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Ga(7)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(5)Se4 tetrahedra, and corners with two equivalent Ga(6)Se4 tetrahedra. In the third Cu site, Cu(3) is bonded to one Se(12), one Se(7), and two equivalent Se(9) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Ga(5)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, corners with two equivalent Ga(6)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. There are seven inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one Se(4), one Se(9), and two equivalent Se(1) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(6)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, and corners with two equivalent Ga(5)Se4 tetrahedra. In the second Ga site, Ga(2) is bonded to one Se(10), one Se(3), and two equivalent Se(5) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(6)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(4)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. In the third Ga site, Ga(3) is bonded to one Se(1), one Se(6), and two equivalent Se(8) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(7)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, and corners with two equivalent Ga(4)Se4 tetrahedra. In the fourth Ga site, Ga(4) is bonded to one Se(2), one Se(8), and two equivalent Se(3) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Ga(5)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, and corners with two equivalent Ga(4)Se4 tetrahedra. In the fifth Ga site, Ga(5) is bonded to one Se(12), one Se(2), and two equivalent Se(4) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Cu(3)Se4 tetrahedra,  a cornercorner with one Ga(4)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, and corners with two equivalent Ga(5)Se4 tetrahedra. In the sixth Ga site, Ga(6) is bonded to one Se(10), one Se(9), and two equivalent Se(11) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(1)Se4 tetrahedra,  a cornercorner with one Ga(2)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, and corners with two equivalent Ga(6)Se4 tetrahedra. In the seventh Ga site, Ga(7) is bonded to one Se(5), one Se(6), and two equivalent Se(7) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Cu(2)Se4 tetrahedra,  a cornercorner with one Ga(3)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. There are twelve inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one Ga(3) and two equivalent Ga(1) atoms. In the second Se site, Se(2) is bonded in a water-like geometry to one Ga(4) and one Ga(5) atom. In the third Se site, Se(3) is bonded in a trigonal non-coplanar geometry to one Ga(2) and two equivalent Ga(4) atoms. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to one Ga(1) and two equivalent Ga(5) atoms. In the fifth Se site, Se(5) is bonded to one Cu(2), one Ga(7), and two equivalent Ga(2) atoms to form SeGa3Cu tetrahedra that share corners with two equivalent Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(5)Ga3Cu tetrahedra, and corners with two equivalent Se(12)GaCu3 tetrahedra. In the sixth Se site, Se(6) is bonded in a water-like geometry to one Ga(3) and one Ga(7) atom. In the seventh Se site, Se(7) is bonded to one Cu(1), one Cu(3), and two equivalent Ga(7) atoms to form SeGa2Cu2 tetrahedra that share  a cornercorner with one Se(8)Ga3Cu tetrahedra,  a cornercorner with one Se(12)GaCu3 tetrahedra, corners with two equivalent Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(9)Ga2Cu2 tetrahedra, and corners with two equivalent Se(5)Ga3Cu tetrahedra. In the eighth Se site, Se(8) is bonded to one Cu(1), one Ga(4), and two equivalent Ga(3) atoms to form SeGa3Cu tetrahedra that share  a cornercorner with one Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(10)Ga2Cu2 tetrahedra, and corners with two equivalent Se(8)Ga3Cu tetrahedra. In the ninth Se site, Se(9) is bonded to two equivalent Cu(3), one Ga(1), and one Ga(6) atom to form SeGa2Cu2 tetrahedra that share  a cornercorner with one Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(9)Ga2Cu2 tetrahedra, and corners with two equivalent Se(12)GaCu3 tetrahedra. In the tenth Se site, Se(10) is bonded to two equivalent Cu(1), one Ga(2), and one Ga(6) atom to form SeGa2Cu2 tetrahedra that share  a cornercorner with one Se(9)Ga2Cu2 tetrahedra, corners with two equivalent Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(5)Ga3Cu tetrahedra, and corners with two equivalent Se(8)Ga3Cu tetrahedra. In the eleventh Se site, Se(11) is bonded in a trigonal non-coplanar geometry to one Cu(2) and two equivalent Ga(6) atoms. In the twelfth Se site, Se(12) is bonded to one Cu(3), two equivalent Cu(2), and one Ga(5) atom to form SeGaCu3 tetrahedra that share  a cornercorner with one Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(9)Ga2Cu2 tetrahedra, corners with two equivalent Se(5)Ga3Cu tetrahedra, and corners with two equivalent Se(12)GaCu3 tetrahedra.
Ga7(CuSe4)3 crystallizes in the monoclinic Cm space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(7), one Se(8), and two equivalent Se(10) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(3)Se4 tetrahedra,  a cornercorner with one Ga(4)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, corners with two equivalent Ga(6)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. The Cu(1)-Se(7) bond length is 2.42 Å. The Cu(1)-Se(8) bond length is 2.44 Å. Both Cu(1)-Se(10) bond lengths are 2.40 Å. In the second Cu site, Cu(2) is bonded to one Se(11), one Se(5), and two equivalent Se(12) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Ga(7)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(5)Se4 tetrahedra, and corners with two equivalent Ga(6)Se4 tetrahedra. The Cu(2)-Se(11) bond length is 2.40 Å. The Cu(2)-Se(5) bond length is 2.47 Å. Both Cu(2)-Se(12) bond lengths are 2.38 Å. In the third Cu site, Cu(3) is bonded to one Se(12), one Se(7), and two equivalent Se(9) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Ga(5)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, corners with two equivalent Ga(6)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. The Cu(3)-Se(12) bond length is 2.37 Å. The Cu(3)-Se(7) bond length is 2.43 Å. Both Cu(3)-Se(9) bond lengths are 2.41 Å. There are seven inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one Se(4), one Se(9), and two equivalent Se(1) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(6)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, and corners with two equivalent Ga(5)Se4 tetrahedra. The Ga(1)-Se(4) bond length is 2.44 Å. The Ga(1)-Se(9) bond length is 2.43 Å. Both Ga(1)-Se(1) bond lengths are 2.51 Å. In the second Ga site, Ga(2) is bonded to one Se(10), one Se(3), and two equivalent Se(5) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(6)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(4)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. The Ga(2)-Se(10) bond length is 2.42 Å. The Ga(2)-Se(3) bond length is 2.46 Å. Both Ga(2)-Se(5) bond lengths are 2.51 Å. In the third Ga site, Ga(3) is bonded to one Se(1), one Se(6), and two equivalent Se(8) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(7)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, and corners with two equivalent Ga(4)Se4 tetrahedra. The Ga(3)-Se(1) bond length is 2.48 Å. The Ga(3)-Se(6) bond length is 2.35 Å. Both Ga(3)-Se(8) bond lengths are 2.53 Å. In the fourth Ga site, Ga(4) is bonded to one Se(2), one Se(8), and two equivalent Se(3) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Ga(5)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, corners with two equivalent Ga(3)Se4 tetrahedra, and corners with two equivalent Ga(4)Se4 tetrahedra. The Ga(4)-Se(2) bond length is 2.33 Å. The Ga(4)-Se(8) bond length is 2.51 Å. Both Ga(4)-Se(3) bond lengths are 2.50 Å. In the fifth Ga site, Ga(5) is bonded to one Se(12), one Se(2), and two equivalent Se(4) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Cu(3)Se4 tetrahedra,  a cornercorner with one Ga(4)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Ga(1)Se4 tetrahedra, and corners with two equivalent Ga(5)Se4 tetrahedra. The Ga(5)-Se(12) bond length is 2.39 Å. The Ga(5)-Se(2) bond length is 2.41 Å. Both Ga(5)-Se(4) bond lengths are 2.53 Å. In the sixth Ga site, Ga(6) is bonded to one Se(10), one Se(9), and two equivalent Se(11) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Ga(1)Se4 tetrahedra,  a cornercorner with one Ga(2)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, and corners with two equivalent Ga(6)Se4 tetrahedra. The Ga(6)-Se(10) bond length is 2.51 Å. The Ga(6)-Se(9) bond length is 2.48 Å. Both Ga(6)-Se(11) bond lengths are 2.42 Å. In the seventh Ga site, Ga(7) is bonded to one Se(5), one Se(6), and two equivalent Se(7) atoms to form GaSe4 tetrahedra that share  a cornercorner with one Cu(2)Se4 tetrahedra,  a cornercorner with one Ga(3)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with two equivalent Ga(2)Se4 tetrahedra, and corners with two equivalent Ga(7)Se4 tetrahedra. The Ga(7)-Se(5) bond length is 2.58 Å. The Ga(7)-Se(6) bond length is 2.37 Å. Both Ga(7)-Se(7) bond lengths are 2.47 Å. There are twelve inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one Ga(3) and two equivalent Ga(1) atoms. In the second Se site, Se(2) is bonded in a water-like geometry to one Ga(4) and one Ga(5) atom. In the third Se site, Se(3) is bonded in a trigonal non-coplanar geometry to one Ga(2) and two equivalent Ga(4) atoms. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to one Ga(1) and two equivalent Ga(5) atoms. In the fifth Se site, Se(5) is bonded to one Cu(2), one Ga(7), and two equivalent Ga(2) atoms to form SeGa3Cu tetrahedra that share corners with two equivalent Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(5)Ga3Cu tetrahedra, and corners with two equivalent Se(12)GaCu3 tetrahedra. In the sixth Se site, Se(6) is bonded in a water-like geometry to one Ga(3) and one Ga(7) atom. In the seventh Se site, Se(7) is bonded to one Cu(1), one Cu(3), and two equivalent Ga(7) atoms to form SeGa2Cu2 tetrahedra that share  a cornercorner with one Se(8)Ga3Cu tetrahedra,  a cornercorner with one Se(12)GaCu3 tetrahedra, corners with two equivalent Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(9)Ga2Cu2 tetrahedra, and corners with two equivalent Se(5)Ga3Cu tetrahedra. In the eighth Se site, Se(8) is bonded to one Cu(1), one Ga(4), and two equivalent Ga(3) atoms to form SeGa3Cu tetrahedra that share  a cornercorner with one Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(10)Ga2Cu2 tetrahedra, and corners with two equivalent Se(8)Ga3Cu tetrahedra. In the ninth Se site, Se(9) is bonded to two equivalent Cu(3), one Ga(1), and one Ga(6) atom to form SeGa2Cu2 tetrahedra that share  a cornercorner with one Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(9)Ga2Cu2 tetrahedra, and corners with two equivalent Se(12)GaCu3 tetrahedra. In the tenth Se site, Se(10) is bonded to two equivalent Cu(1), one Ga(2), and one Ga(6) atom to form SeGa2Cu2 tetrahedra that share  a cornercorner with one Se(9)Ga2Cu2 tetrahedra, corners with two equivalent Se(10)Ga2Cu2 tetrahedra, corners with two equivalent Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(5)Ga3Cu tetrahedra, and corners with two equivalent Se(8)Ga3Cu tetrahedra. In the eleventh Se site, Se(11) is bonded in a trigonal non-coplanar geometry to one Cu(2) and two equivalent Ga(6) atoms. In the twelfth Se site, Se(12) is bonded to one Cu(3), two equivalent Cu(2), and one Ga(5) atom to form SeGaCu3 tetrahedra that share  a cornercorner with one Se(7)Ga2Cu2 tetrahedra, corners with two equivalent Se(9)Ga2Cu2 tetrahedra, corners with two equivalent Se(5)Ga3Cu tetrahedra, and corners with two equivalent Se(12)GaCu3 tetrahedra.