MgCr2(FeO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. Cr(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form edge-sharing FeO6 octahedra. In the second Fe site, Fe(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form edge-sharing FeO6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Fe(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(1) and one Fe(2) atom.
MgCr2(FeO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. Both Mg(1)-O(2) bond lengths are 2.52 Å. All Mg(1)-O(1) bond lengths are 2.07 Å. Cr(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(1) atoms. The Cr(1)-O(2) bond length is 1.74 Å. The Cr(1)-O(3) bond length is 1.71 Å. Both Cr(1)-O(1) bond lengths are 1.94 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form edge-sharing FeO6 octahedra. Both Fe(1)-O(2) bond lengths are 1.97 Å. All Fe(1)-O(1) bond lengths are 2.13 Å. In the second Fe site, Fe(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form edge-sharing FeO6 octahedra. Both Fe(2)-O(3) bond lengths are 1.98 Å. All Fe(2)-O(1) bond lengths are 2.11 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Fe(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(1) and one Fe(2) atom.