MgCu2O4 is Spinel structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form MgO4 tetrahedra that share corners with three equivalent Cu(2)O6 octahedra, corners with three equivalent Cu(3)O6 octahedra, and corners with six equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-61°. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CuO6 octahedra that share corners with six equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cu(1)O6 octahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with two equivalent Cu(3)O6 octahedra. In the second Cu site, Cu(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CuO6 octahedra that share corners with six equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cu(3)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. In the third Cu site, Cu(3) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CuO6 octahedra that share corners with six equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Cu(1), one Cu(2), and one Cu(3) atom to form a mixture of distorted corner and edge-sharing OMgCu3 trigonal pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(3), and two equivalent Cu(1) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(2), and two equivalent Cu(1) atoms.
MgCu2O4 is Spinel structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form MgO4 tetrahedra that share corners with three equivalent Cu(2)O6 octahedra, corners with three equivalent Cu(3)O6 octahedra, and corners with six equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-61°. The Mg(1)-O(2) bond length is 1.99 Å. The Mg(1)-O(3) bond length is 1.97 Å. Both Mg(1)-O(1) bond lengths are 2.00 Å. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CuO6 octahedra that share corners with six equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cu(1)O6 octahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with two equivalent Cu(3)O6 octahedra. Both Cu(1)-O(1) bond lengths are 2.03 Å. Both Cu(1)-O(2) bond lengths are 2.01 Å. Both Cu(1)-O(3) bond lengths are 1.97 Å. In the second Cu site, Cu(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CuO6 octahedra that share corners with six equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cu(3)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. Both Cu(2)-O(3) bond lengths are 2.14 Å. All Cu(2)-O(1) bond lengths are 1.95 Å. In the third Cu site, Cu(3) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CuO6 octahedra that share corners with six equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. Both Cu(3)-O(2) bond lengths are 2.00 Å. All Cu(3)-O(1) bond lengths are 2.01 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Cu(1), one Cu(2), and one Cu(3) atom to form a mixture of distorted corner and edge-sharing OMgCu3 trigonal pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(3), and two equivalent Cu(1) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(2), and two equivalent Cu(1) atoms.