MgCu4(SO5)2 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(5), and two equivalent O(3) atoms. In the second Cu site, Cu(2) is bonded to one O(1), one O(2), one O(4), and two equivalent O(3) atoms to form distorted CuO5 trigonal bipyramids that share corners with three equivalent S(1)O4 tetrahedra and corners with two equivalent Cu(2)O5 trigonal bipyramids. S(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form SO4 tetrahedra that share corners with three equivalent Cu(2)O5 trigonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(2), and one S(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one S(1) atom. In the third O site, O(3) is bonded to one Mg(1), two equivalent Cu(1), and two equivalent Cu(2) atoms to form a mixture of distorted face and corner-sharing OMgCu4 square pyramids. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(2), and one S(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cu(1) and one S(1) atom.
MgCu4(SO5)2 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Both Mg(1)-O(1) bond lengths are 2.17 Å. Both Mg(1)-O(3) bond lengths are 2.10 Å. Both Mg(1)-O(4) bond lengths are 2.13 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(5), and two equivalent O(3) atoms. The Cu(1)-O(2) bond length is 2.00 Å. The Cu(1)-O(5) bond length is 2.02 Å. There is one shorter (2.00 Å) and one longer (2.14 Å) Cu(1)-O(3) bond length. In the second Cu site, Cu(2) is bonded to one O(1), one O(2), one O(4), and two equivalent O(3) atoms to form distorted CuO5 trigonal bipyramids that share corners with three equivalent S(1)O4 tetrahedra and corners with two equivalent Cu(2)O5 trigonal bipyramids. The Cu(2)-O(1) bond length is 2.33 Å. The Cu(2)-O(2) bond length is 2.24 Å. The Cu(2)-O(4) bond length is 2.43 Å. Both Cu(2)-O(3) bond lengths are 2.01 Å. S(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form SO4 tetrahedra that share corners with three equivalent Cu(2)O5 trigonal bipyramids. The S(1)-O(1) bond length is 1.50 Å. The S(1)-O(2) bond length is 1.52 Å. The S(1)-O(4) bond length is 1.52 Å. The S(1)-O(5) bond length is 1.46 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(2), and one S(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one S(1) atom. In the third O site, O(3) is bonded to one Mg(1), two equivalent Cu(1), and two equivalent Cu(2) atoms to form a mixture of distorted face and corner-sharing OMgCu4 square pyramids. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(2), and one S(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cu(1) and one S(1) atom.