MgWCu2S4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form distorted MgS4 tetrahedra that share corners with eight equivalent Cu(1)W2S4 tetrahedra. W(1) is bonded in a 8-coordinate geometry to four equivalent Cu(1), one S(2), one S(3), and two equivalent S(1) atoms. Cu(1) is bonded to two equivalent W(1), one S(2), one S(3), and two equivalent S(1) atoms to form distorted CuW2S4 tetrahedra that share corners with two equivalent Cu(1)W2S4 tetrahedra, corners with four equivalent Mg(1)S4 tetrahedra, corners with four equivalent S(1)MgCu2W tetrahedra, and edges with four equivalent Cu(1)W2S4 tetrahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one W(1), and two equivalent Cu(1) atoms to form distorted SMgCu2W tetrahedra that share corners with four equivalent Cu(1)W2S4 tetrahedra and corners with four equivalent S(1)MgCu2W tetrahedra. In the second S site, S(2) is bonded in a 4-coordinate geometry to one Mg(1), one W(1), and two equivalent Cu(1) atoms. In the third S site, S(3) is bonded in a 4-coordinate geometry to one Mg(1), one W(1), and two equivalent Cu(1) atoms.
MgWCu2S4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form distorted MgS4 tetrahedra that share corners with eight equivalent Cu(1)W2S4 tetrahedra. The Mg(1)-S(2) bond length is 2.47 Å. The Mg(1)-S(3) bond length is 2.47 Å. Both Mg(1)-S(1) bond lengths are 2.55 Å. W(1) is bonded in a 8-coordinate geometry to four equivalent Cu(1), one S(2), one S(3), and two equivalent S(1) atoms. All W(1)-Cu(1) bond lengths are 2.72 Å. The W(1)-S(2) bond length is 2.35 Å. The W(1)-S(3) bond length is 2.35 Å. Both W(1)-S(1) bond lengths are 2.26 Å. Cu(1) is bonded to two equivalent W(1), one S(2), one S(3), and two equivalent S(1) atoms to form distorted CuW2S4 tetrahedra that share corners with two equivalent Cu(1)W2S4 tetrahedra, corners with four equivalent Mg(1)S4 tetrahedra, corners with four equivalent S(1)MgCu2W tetrahedra, and edges with four equivalent Cu(1)W2S4 tetrahedra. The Cu(1)-S(2) bond length is 2.37 Å. The Cu(1)-S(3) bond length is 2.37 Å. There is one shorter (2.36 Å) and one longer (2.37 Å) Cu(1)-S(1) bond length. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one W(1), and two equivalent Cu(1) atoms to form distorted SMgCu2W tetrahedra that share corners with four equivalent Cu(1)W2S4 tetrahedra and corners with four equivalent S(1)MgCu2W tetrahedra. In the second S site, S(2) is bonded in a 4-coordinate geometry to one Mg(1), one W(1), and two equivalent Cu(1) atoms. In the third S site, S(3) is bonded in a 4-coordinate geometry to one Mg(1), one W(1), and two equivalent Cu(1) atoms.