MgIn2(FeO3)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent In(1)O6 octahedra, corners with three equivalent Fe(2)O4 trigonal pyramids, edges with three equivalent In(1)O6 octahedra, edges with six equivalent Mg(1)O6 octahedra, and edges with three equivalent Fe(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 8-10°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), one O(6), and three equivalent O(1) atoms to form FeO5 trigonal bipyramids that share corners with three equivalent In(1)O6 octahedra, corners with three equivalent In(2)O6 octahedra, and corners with six equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 62-66°. In the second Fe site, Fe(2) is bonded to one O(5) and three equivalent O(2) atoms to form distorted FeO4 trigonal pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent In(2)O6 octahedra, corners with six equivalent Fe(2)O4 trigonal pyramids, and edges with three equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-62°. There are two inequivalent In sites. In the first In site, In(1) is bonded to three equivalent O(3) and three equivalent O(6) atoms to form distorted InO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Fe(1)O5 trigonal bipyramids, edges with three equivalent Mg(1)O6 octahedra, and edges with six equivalent In(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-10°. In the second In site, In(2) is bonded to three equivalent O(4) and three equivalent O(5) atoms to form InO6 octahedra that share corners with three equivalent Fe(1)O5 trigonal bipyramids, corners with three equivalent Fe(2)O4 trigonal pyramids, and edges with six equivalent In(2)O6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to three equivalent Fe(1) atoms. In the second O site, O(2) is bonded to three equivalent Mg(1) and three equivalent Fe(2) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(3)Mg3In3 octahedra, edges with three equivalent O(3)Mg3In3 octahedra, and edges with six equivalent O(2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 3-4°. In the third O site, O(3) is bonded to three equivalent Mg(1) and three equivalent In(1) atoms to form OMg3In3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra, corners with three equivalent O(6)In3Fe tetrahedra, edges with three equivalent O(2)Mg3Fe3 octahedra, edges with six equivalent O(3)Mg3In3 octahedra, and edges with three equivalent O(6)In3Fe tetrahedra. The corner-sharing octahedral tilt angles range from 3-4°. In the fourth O site, O(4) is bonded to one Fe(1) and three equivalent In(2) atoms to form corner-sharing OIn3Fe tetrahedra. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Fe(2) and three equivalent In(2) atoms. In the sixth O site, O(6) is bonded to one Fe(1) and three equivalent In(1) atoms to form OIn3Fe tetrahedra that share corners with three equivalent O(3)Mg3In3 octahedra,  a cornercorner with one O(4)In3Fe tetrahedra, corners with six equivalent O(6)In3Fe tetrahedra, and edges with three equivalent O(3)Mg3In3 octahedra. The corner-sharing octahedral tilt angles range from 15-16°.
MgIn2(FeO3)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent In(1)O6 octahedra, corners with three equivalent Fe(2)O4 trigonal pyramids, edges with three equivalent In(1)O6 octahedra, edges with six equivalent Mg(1)O6 octahedra, and edges with three equivalent Fe(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 8-10°. There is one shorter (2.20 Å) and two longer (2.31 Å) Mg(1)-O(2) bond lengths. There are two shorter (2.21 Å) and one longer (2.25 Å) Mg(1)-O(3) bond length. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), one O(6), and three equivalent O(1) atoms to form FeO5 trigonal bipyramids that share corners with three equivalent In(1)O6 octahedra, corners with three equivalent In(2)O6 octahedra, and corners with six equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 62-66°. The Fe(1)-O(4) bond length is 2.10 Å. The Fe(1)-O(6) bond length is 2.35 Å. There are two shorter (1.92 Å) and one longer (1.96 Å) Fe(1)-O(1) bond length. In the second Fe site, Fe(2) is bonded to one O(5) and three equivalent O(2) atoms to form distorted FeO4 trigonal pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent In(2)O6 octahedra, corners with six equivalent Fe(2)O4 trigonal pyramids, and edges with three equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-62°. The Fe(2)-O(5) bond length is 1.92 Å. There are two shorter (2.19 Å) and one longer (2.39 Å) Fe(2)-O(2) bond length. There are two inequivalent In sites. In the first In site, In(1) is bonded to three equivalent O(3) and three equivalent O(6) atoms to form distorted InO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Fe(1)O5 trigonal bipyramids, edges with three equivalent Mg(1)O6 octahedra, and edges with six equivalent In(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-10°. There is one shorter (2.43 Å) and two longer (2.49 Å) In(1)-O(3) bond lengths. All In(1)-O(6) bond lengths are 2.10 Å. In the second In site, In(2) is bonded to three equivalent O(4) and three equivalent O(5) atoms to form InO6 octahedra that share corners with three equivalent Fe(1)O5 trigonal bipyramids, corners with three equivalent Fe(2)O4 trigonal pyramids, and edges with six equivalent In(2)O6 octahedra. All In(2)-O(4) bond lengths are 2.18 Å. There is one shorter (2.25 Å) and two longer (2.27 Å) In(2)-O(5) bond lengths. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to three equivalent Fe(1) atoms. In the second O site, O(2) is bonded to three equivalent Mg(1) and three equivalent Fe(2) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(3)Mg3In3 octahedra, edges with three equivalent O(3)Mg3In3 octahedra, and edges with six equivalent O(2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 3-4°. In the third O site, O(3) is bonded to three equivalent Mg(1) and three equivalent In(1) atoms to form OMg3In3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra, corners with three equivalent O(6)In3Fe tetrahedra, edges with three equivalent O(2)Mg3Fe3 octahedra, edges with six equivalent O(3)Mg3In3 octahedra, and edges with three equivalent O(6)In3Fe tetrahedra. The corner-sharing octahedral tilt angles range from 3-4°. In the fourth O site, O(4) is bonded to one Fe(1) and three equivalent In(2) atoms to form corner-sharing OIn3Fe tetrahedra. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Fe(2) and three equivalent In(2) atoms. In the sixth O site, O(6) is bonded to one Fe(1) and three equivalent In(1) atoms to form OIn3Fe tetrahedra that share corners with three equivalent O(3)Mg3In3 octahedra,  a cornercorner with one O(4)In3Fe tetrahedra, corners with six equivalent O(6)In3Fe tetrahedra, and edges with three equivalent O(3)Mg3In3 octahedra. The corner-sharing octahedral tilt angles range from 15-16°.