MgCr2Cd2O8 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. Cr(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted CrO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra and corners with three equivalent Cd(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-65°. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CdO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and edges with two equivalent Cd(2)O6 octahedra. In the second Cd site, Cd(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CdO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and edges with two equivalent Cd(1)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Cd(1), and one Cd(2) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cd(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Cd(1) atom.
MgCr2Cd2O8 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. Both Mg(1)-O(3) bond lengths are 2.28 Å. All Mg(1)-O(1) bond lengths are 2.19 Å. Cr(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted CrO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra and corners with three equivalent Cd(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-65°. The Cr(1)-O(2) bond length is 1.65 Å. The Cr(1)-O(3) bond length is 1.74 Å. Both Cr(1)-O(1) bond lengths are 1.78 Å. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CdO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and edges with two equivalent Cd(2)O6 octahedra. Both Cd(1)-O(3) bond lengths are 2.27 Å. All Cd(1)-O(1) bond lengths are 2.40 Å. In the second Cd site, Cd(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CdO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and edges with two equivalent Cd(1)O6 octahedra. Both Cd(2)-O(2) bond lengths are 2.19 Å. All Cd(2)-O(1) bond lengths are 2.44 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Cd(1), and one Cd(2) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cd(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Cd(1) atom.