MgCr2(FeO4)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 4-coordinate geometry to one O(2), one O(6), and two equivalent O(4) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(5), and two equivalent O(3) atoms. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(2), one O(6), and two equivalent O(4) atoms. Fe(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(5), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(2), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(1) and one Fe(1) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to one Mg(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(2), and two equivalent Fe(1) atoms.
MgCr2(FeO4)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 4-coordinate geometry to one O(2), one O(6), and two equivalent O(4) atoms. The Mg(1)-O(2) bond length is 1.97 Å. The Mg(1)-O(6) bond length is 1.97 Å. Both Mg(1)-O(4) bond lengths are 1.99 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(5), and two equivalent O(3) atoms. The Cr(1)-O(1) bond length is 1.77 Å. The Cr(1)-O(5) bond length is 1.76 Å. Both Cr(1)-O(3) bond lengths are 1.73 Å. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(2), one O(6), and two equivalent O(4) atoms. The Cr(2)-O(2) bond length is 1.76 Å. The Cr(2)-O(6) bond length is 1.76 Å. Both Cr(2)-O(4) bond lengths are 1.70 Å. Fe(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(5), and one O(6) atom. The Fe(1)-O(1) bond length is 2.15 Å. The Fe(1)-O(2) bond length is 2.29 Å. The Fe(1)-O(3) bond length is 1.98 Å. The Fe(1)-O(5) bond length is 2.15 Å. The Fe(1)-O(6) bond length is 2.29 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(2), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(1) and one Fe(1) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to one Mg(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(2), and two equivalent Fe(1) atoms.