Mg(CuS2)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 7-coordinate geometry to two equivalent Cu(2), one S(2), two equivalent S(1), and two equivalent S(4) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one S(1), one S(4), two equivalent S(2), and two equivalent S(3) atoms to form edge-sharing CuS6 octahedra. In the second Cu site, Cu(2) is bonded in a 7-coordinate geometry to two equivalent Mg(1), one S(3), two equivalent S(1), and two equivalent S(4) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(1), and two equivalent Cu(2) atoms. In the second S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Cu(1), and one S(3) atom. In the third S site, S(3) is bonded in a 4-coordinate geometry to one Cu(2), two equivalent Cu(1), and one S(2) atom. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(1), and two equivalent Cu(2) atoms.
Mg(CuS2)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 7-coordinate geometry to two equivalent Cu(2), one S(2), two equivalent S(1), and two equivalent S(4) atoms. There is one shorter (2.73 Å) and one longer (2.80 Å) Mg(1)-Cu(2) bond length. The Mg(1)-S(2) bond length is 2.51 Å. Both Mg(1)-S(1) bond lengths are 2.53 Å. Both Mg(1)-S(4) bond lengths are 2.60 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one S(1), one S(4), two equivalent S(2), and two equivalent S(3) atoms to form edge-sharing CuS6 octahedra. The Cu(1)-S(1) bond length is 2.32 Å. The Cu(1)-S(4) bond length is 2.35 Å. Both Cu(1)-S(2) bond lengths are 2.54 Å. Both Cu(1)-S(3) bond lengths are 2.57 Å. In the second Cu site, Cu(2) is bonded in a 7-coordinate geometry to two equivalent Mg(1), one S(3), two equivalent S(1), and two equivalent S(4) atoms. The Cu(2)-S(3) bond length is 2.53 Å. Both Cu(2)-S(1) bond lengths are 2.38 Å. Both Cu(2)-S(4) bond lengths are 2.42 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(1), and two equivalent Cu(2) atoms. In the second S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Cu(1), and one S(3) atom. The S(2)-S(3) bond length is 2.05 Å. In the third S site, S(3) is bonded in a 4-coordinate geometry to one Cu(2), two equivalent Cu(1), and one S(2) atom. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(1), and two equivalent Cu(2) atoms.