MgFe2O5 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with six equivalent Fe(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-65°. Fe(1) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1) and three equivalent Fe(1) atoms to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one O(3)Mg2Fe2 trigonal pyramid, corners with three equivalent O(1)MgFe3 trigonal pyramids, edges with two equivalent O(3)Mg2Fe2 trigonal pyramids, and edges with two equivalent O(1)MgFe3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(1) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded to two equivalent Mg(1) and two equivalent Fe(1) atoms to form distorted OMg2Fe2 trigonal pyramids that share corners with two equivalent O(3)Mg2Fe2 trigonal pyramids, corners with two equivalent O(1)MgFe3 trigonal pyramids, and edges with four equivalent O(1)MgFe3 trigonal pyramids.
MgFe2O5 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with six equivalent Fe(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-65°. Both Mg(1)-O(1) bond lengths are 2.09 Å. Both Mg(1)-O(2) bond lengths are 2.09 Å. Both Mg(1)-O(3) bond lengths are 2.11 Å. Fe(1) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. The Fe(1)-O(3) bond length is 2.00 Å. There is one shorter (1.89 Å) and one longer (1.90 Å) Fe(1)-O(2) bond length. There are a spread of Fe(1)-O(1) bond distances ranging from 1.98-2.20 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1) and three equivalent Fe(1) atoms to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one O(3)Mg2Fe2 trigonal pyramid, corners with three equivalent O(1)MgFe3 trigonal pyramids, edges with two equivalent O(3)Mg2Fe2 trigonal pyramids, and edges with two equivalent O(1)MgFe3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(1) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded to two equivalent Mg(1) and two equivalent Fe(1) atoms to form distorted OMg2Fe2 trigonal pyramids that share corners with two equivalent O(3)Mg2Fe2 trigonal pyramids, corners with two equivalent O(1)MgFe3 trigonal pyramids, and edges with four equivalent O(1)MgFe3 trigonal pyramids.