MgV2(FeO2)4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(5) atoms. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(5) atoms to form VO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, corners with two equivalent Fe(3)O5 trigonal bipyramids, edges with two equivalent V(2)O6 octahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. In the second V site, V(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form VO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, corners with two equivalent Fe(3)O5 trigonal bipyramids, edges with two equivalent V(1)O6 octahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), one O(6), and two equivalent O(5) atoms to form distorted FeO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra, corners with three equivalent V(2)O6 octahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with six equivalent Fe(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 54-77°. In the second Fe site, Fe(2) is bonded to one O(4), one O(6), and two equivalent O(1) atoms to form distorted FeO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra, corners with three equivalent V(2)O6 octahedra, corners with two equivalent Fe(1)O4 tetrahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 30-64°. In the third Fe site, Fe(3) is bonded to one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one V(1)O6 octahedra,  a cornercorner with one V(2)O6 octahedra, corners with three equivalent Fe(1)O4 tetrahedra,  an edgeedge with one V(1)O6 octahedra,  an edgeedge with one V(2)O6 octahedra,  an edgeedge with one Fe(2)O4 tetrahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one V(1), one V(2), and one Fe(2) atom. In the second O site, O(2) is bonded to one Mg(1), one V(1), and two equivalent Fe(3) atoms to form distorted OMgVFe2 tetrahedra that share  a cornercorner with one O(3)MgVFe2 tetrahedra, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, corners with two equivalent O(4)VFe4 trigonal bipyramids, corners with three equivalent O(6)VFe4 trigonal bipyramids,  an edgeedge with one O(3)MgVFe2 tetrahedra, and edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids. In the third O site, O(3) is bonded to one Mg(1), one V(2), and two equivalent Fe(3) atoms to form distorted OMgVFe2 tetrahedra that share  a cornercorner with one O(2)MgVFe2 tetrahedra, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, corners with two equivalent O(6)VFe4 trigonal bipyramids, corners with three equivalent O(4)VFe4 trigonal bipyramids,  an edgeedge with one O(2)MgVFe2 tetrahedra, and edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one V(2), one Fe(1), one Fe(2), and two equivalent Fe(3) atoms to form distorted OVFe4 trigonal bipyramids that share corners with two equivalent O(2)MgVFe2 tetrahedra, corners with three equivalent O(3)MgVFe2 tetrahedra,  a cornercorner with one O(6)VFe4 trigonal bipyramid, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids, and  a faceface with one O(6)VFe4 trigonal bipyramid. In the fifth O site, O(5) is bonded to one Mg(1), one V(1), one V(2), one Fe(1), and one Fe(3) atom to form distorted OMgV2Fe2 trigonal bipyramids that share  a cornercorner with one O(2)MgVFe2 tetrahedra,  a cornercorner with one O(3)MgVFe2 tetrahedra,  a cornercorner with one O(5)MgV2Fe2 trigonal bipyramid,  a cornercorner with one O(4)VFe4 trigonal bipyramid,  a cornercorner with one O(6)VFe4 trigonal bipyramid,  an edgeedge with one O(2)MgVFe2 tetrahedra,  an edgeedge with one O(3)MgVFe2 tetrahedra,  an edgeedge with one O(4)VFe4 trigonal bipyramid,  an edgeedge with one O(6)VFe4 trigonal bipyramid, and  a faceface with one O(5)MgV2Fe2 trigonal bipyramid. In the sixth O site, O(6) is bonded to one V(1), one Fe(1), one Fe(2), and two equivalent Fe(3) atoms to form distorted OVFe4 trigonal bipyramids that share corners with two equivalent O(3)MgVFe2 tetrahedra, corners with three equivalent O(2)MgVFe2 tetrahedra,  a cornercorner with one O(4)VFe4 trigonal bipyramid, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids, and  a faceface with one O(4)VFe4 trigonal bipyramid.
MgV2(FeO2)4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(5) atoms. The Mg(1)-O(2) bond length is 1.94 Å. The Mg(1)-O(3) bond length is 1.94 Å. Both Mg(1)-O(1) bond lengths are 2.30 Å. Both Mg(1)-O(5) bond lengths are 2.45 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(5) atoms to form VO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, corners with two equivalent Fe(3)O5 trigonal bipyramids, edges with two equivalent V(2)O6 octahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. The V(1)-O(2) bond length is 1.99 Å. The V(1)-O(6) bond length is 2.03 Å. Both V(1)-O(1) bond lengths are 2.15 Å. Both V(1)-O(5) bond lengths are 2.15 Å. In the second V site, V(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form VO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, corners with two equivalent Fe(3)O5 trigonal bipyramids, edges with two equivalent V(1)O6 octahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. The V(2)-O(3) bond length is 1.99 Å. The V(2)-O(4) bond length is 2.05 Å. Both V(2)-O(1) bond lengths are 2.14 Å. Both V(2)-O(5) bond lengths are 2.15 Å. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), one O(6), and two equivalent O(5) atoms to form distorted FeO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra, corners with three equivalent V(2)O6 octahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with six equivalent Fe(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 54-77°. The Fe(1)-O(4) bond length is 2.04 Å. The Fe(1)-O(6) bond length is 2.03 Å. Both Fe(1)-O(5) bond lengths are 2.16 Å. In the second Fe site, Fe(2) is bonded to one O(4), one O(6), and two equivalent O(1) atoms to form distorted FeO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra, corners with three equivalent V(2)O6 octahedra, corners with two equivalent Fe(1)O4 tetrahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 30-64°. The Fe(2)-O(4) bond length is 2.15 Å. The Fe(2)-O(6) bond length is 2.12 Å. Both Fe(2)-O(1) bond lengths are 1.97 Å. In the third Fe site, Fe(3) is bonded to one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one V(1)O6 octahedra,  a cornercorner with one V(2)O6 octahedra, corners with three equivalent Fe(1)O4 tetrahedra,  an edgeedge with one V(1)O6 octahedra,  an edgeedge with one V(2)O6 octahedra,  an edgeedge with one Fe(2)O4 tetrahedra, and edges with two equivalent Fe(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. The Fe(3)-O(2) bond length is 2.03 Å. The Fe(3)-O(3) bond length is 2.02 Å. The Fe(3)-O(4) bond length is 2.19 Å. The Fe(3)-O(5) bond length is 2.05 Å. The Fe(3)-O(6) bond length is 2.23 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one V(1), one V(2), and one Fe(2) atom. In the second O site, O(2) is bonded to one Mg(1), one V(1), and two equivalent Fe(3) atoms to form distorted OMgVFe2 tetrahedra that share  a cornercorner with one O(3)MgVFe2 tetrahedra, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, corners with two equivalent O(4)VFe4 trigonal bipyramids, corners with three equivalent O(6)VFe4 trigonal bipyramids,  an edgeedge with one O(3)MgVFe2 tetrahedra, and edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids. In the third O site, O(3) is bonded to one Mg(1), one V(2), and two equivalent Fe(3) atoms to form distorted OMgVFe2 tetrahedra that share  a cornercorner with one O(2)MgVFe2 tetrahedra, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, corners with two equivalent O(6)VFe4 trigonal bipyramids, corners with three equivalent O(4)VFe4 trigonal bipyramids,  an edgeedge with one O(2)MgVFe2 tetrahedra, and edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one V(2), one Fe(1), one Fe(2), and two equivalent Fe(3) atoms to form distorted OVFe4 trigonal bipyramids that share corners with two equivalent O(2)MgVFe2 tetrahedra, corners with three equivalent O(3)MgVFe2 tetrahedra,  a cornercorner with one O(6)VFe4 trigonal bipyramid, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids, and  a faceface with one O(6)VFe4 trigonal bipyramid. In the fifth O site, O(5) is bonded to one Mg(1), one V(1), one V(2), one Fe(1), and one Fe(3) atom to form distorted OMgV2Fe2 trigonal bipyramids that share  a cornercorner with one O(2)MgVFe2 tetrahedra,  a cornercorner with one O(3)MgVFe2 tetrahedra,  a cornercorner with one O(5)MgV2Fe2 trigonal bipyramid,  a cornercorner with one O(4)VFe4 trigonal bipyramid,  a cornercorner with one O(6)VFe4 trigonal bipyramid,  an edgeedge with one O(2)MgVFe2 tetrahedra,  an edgeedge with one O(3)MgVFe2 tetrahedra,  an edgeedge with one O(4)VFe4 trigonal bipyramid,  an edgeedge with one O(6)VFe4 trigonal bipyramid, and  a faceface with one O(5)MgV2Fe2 trigonal bipyramid. In the sixth O site, O(6) is bonded to one V(1), one Fe(1), one Fe(2), and two equivalent Fe(3) atoms to form distorted OVFe4 trigonal bipyramids that share corners with two equivalent O(3)MgVFe2 tetrahedra, corners with three equivalent O(2)MgVFe2 tetrahedra,  a cornercorner with one O(4)VFe4 trigonal bipyramid, corners with two equivalent O(5)MgV2Fe2 trigonal bipyramids, edges with two equivalent O(5)MgV2Fe2 trigonal bipyramids, and  a faceface with one O(4)VFe4 trigonal bipyramid.