MgTi2(Fe2O5)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(2), and four equivalent O(4) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids, and edges with four equivalent Fe(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 39°. In the second Ti site, Ti(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra and corners with two equivalent Fe(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with three equivalent Fe(2)O5 trigonal bipyramids, and edges with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-66°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ti(1), one Fe(1), and two equivalent Fe(2) atoms to form distorted OTiFe3 trigonal pyramids that share  a cornercorner with one O(6)MgTi2Fe2 trigonal bipyramid, corners with three equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with two equivalent O(2)MgTiFe2 trigonal pyramids, corners with three equivalent O(1)TiFe3 trigonal pyramids, and edges with two equivalent O(5)Ti2Fe2 tetrahedra. In the second O site, O(2) is bonded to one Mg(1), one Ti(2), and two equivalent Fe(1) atoms to form OMgTiFe2 trigonal pyramids that share  a cornercorner with one O(6)MgTi2Fe2 trigonal bipyramid, corners with four equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with two equivalent O(2)MgTiFe2 trigonal pyramids, corners with two equivalent O(1)TiFe3 trigonal pyramids, edges with two equivalent O(4)Mg2TiFe2 trigonal bipyramids, edges with two equivalent O(6)MgTi2Fe2 trigonal bipyramids, and  an edgeedge with one O(2)MgTiFe2 trigonal pyramid. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ti(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded to two equivalent Mg(1), one Ti(2), one Fe(1), and one Fe(2) atom to form distorted OMg2TiFe2 trigonal bipyramids that share  a cornercorner with one O(5)Ti2Fe2 tetrahedra,  a cornercorner with one O(6)MgTi2Fe2 trigonal bipyramid, corners with four equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with three equivalent O(1)TiFe3 trigonal pyramids, corners with four equivalent O(2)MgTiFe2 trigonal pyramids, edges with two equivalent O(6)MgTi2Fe2 trigonal bipyramids, edges with two equivalent O(2)MgTiFe2 trigonal pyramids, and  a faceface with one O(4)Mg2TiFe2 trigonal bipyramid. In the fifth O site, O(5) is bonded to two equivalent Ti(1) and two equivalent Fe(2) atoms to form distorted OTi2Fe2 tetrahedra that share corners with two equivalent O(5)Ti2Fe2 tetrahedra, corners with two equivalent O(4)Mg2TiFe2 trigonal bipyramids, and edges with four equivalent O(1)TiFe3 trigonal pyramids. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Ti(2), and two equivalent Fe(1) atoms to form distorted OMgTi2Fe2 trigonal bipyramids that share corners with two equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with two equivalent O(6)MgTi2Fe2 trigonal bipyramids, corners with two equivalent O(2)MgTiFe2 trigonal pyramids, corners with two equivalent O(1)TiFe3 trigonal pyramids, edges with four equivalent O(4)Mg2TiFe2 trigonal bipyramids, and edges with four equivalent O(2)MgTiFe2 trigonal pyramids.
MgTi2(Fe2O5)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(2), and four equivalent O(4) atoms. The Mg(1)-O(6) bond length is 2.11 Å. Both Mg(1)-O(2) bond lengths are 2.11 Å. There are two shorter (2.32 Å) and two longer (2.46 Å) Mg(1)-O(4) bond lengths. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids, and edges with four equivalent Fe(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 39°. Both Ti(1)-O(1) bond lengths are 2.16 Å. Both Ti(1)-O(3) bond lengths are 1.88 Å. There is one shorter (2.01 Å) and one longer (2.02 Å) Ti(1)-O(5) bond length. In the second Ti site, Ti(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra and corners with two equivalent Fe(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 1°. Both Ti(2)-O(2) bond lengths are 1.97 Å. Both Ti(2)-O(4) bond lengths are 1.99 Å. There is one shorter (1.87 Å) and one longer (1.93 Å) Ti(2)-O(6) bond length. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms. The Fe(1)-O(1) bond length is 2.22 Å. The Fe(1)-O(3) bond length is 2.04 Å. The Fe(1)-O(4) bond length is 2.22 Å. The Fe(1)-O(6) bond length is 2.56 Å. There is one shorter (2.00 Å) and one longer (2.02 Å) Fe(1)-O(2) bond length. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with three equivalent Fe(2)O5 trigonal bipyramids, and edges with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 23-66°. The Fe(2)-O(3) bond length is 1.90 Å. The Fe(2)-O(4) bond length is 2.02 Å. The Fe(2)-O(5) bond length is 2.24 Å. There is one shorter (2.01 Å) and one longer (2.02 Å) Fe(2)-O(1) bond length. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ti(1), one Fe(1), and two equivalent Fe(2) atoms to form distorted OTiFe3 trigonal pyramids that share  a cornercorner with one O(6)MgTi2Fe2 trigonal bipyramid, corners with three equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with two equivalent O(2)MgTiFe2 trigonal pyramids, corners with three equivalent O(1)TiFe3 trigonal pyramids, and edges with two equivalent O(5)Ti2Fe2 tetrahedra. In the second O site, O(2) is bonded to one Mg(1), one Ti(2), and two equivalent Fe(1) atoms to form OMgTiFe2 trigonal pyramids that share  a cornercorner with one O(6)MgTi2Fe2 trigonal bipyramid, corners with four equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with two equivalent O(2)MgTiFe2 trigonal pyramids, corners with two equivalent O(1)TiFe3 trigonal pyramids, edges with two equivalent O(4)Mg2TiFe2 trigonal bipyramids, edges with two equivalent O(6)MgTi2Fe2 trigonal bipyramids, and  an edgeedge with one O(2)MgTiFe2 trigonal pyramid. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ti(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded to two equivalent Mg(1), one Ti(2), one Fe(1), and one Fe(2) atom to form distorted OMg2TiFe2 trigonal bipyramids that share  a cornercorner with one O(5)Ti2Fe2 tetrahedra,  a cornercorner with one O(6)MgTi2Fe2 trigonal bipyramid, corners with four equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with three equivalent O(1)TiFe3 trigonal pyramids, corners with four equivalent O(2)MgTiFe2 trigonal pyramids, edges with two equivalent O(6)MgTi2Fe2 trigonal bipyramids, edges with two equivalent O(2)MgTiFe2 trigonal pyramids, and  a faceface with one O(4)Mg2TiFe2 trigonal bipyramid. In the fifth O site, O(5) is bonded to two equivalent Ti(1) and two equivalent Fe(2) atoms to form distorted OTi2Fe2 tetrahedra that share corners with two equivalent O(5)Ti2Fe2 tetrahedra, corners with two equivalent O(4)Mg2TiFe2 trigonal bipyramids, and edges with four equivalent O(1)TiFe3 trigonal pyramids. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Ti(2), and two equivalent Fe(1) atoms to form distorted OMgTi2Fe2 trigonal bipyramids that share corners with two equivalent O(4)Mg2TiFe2 trigonal bipyramids, corners with two equivalent O(6)MgTi2Fe2 trigonal bipyramids, corners with two equivalent O(2)MgTiFe2 trigonal pyramids, corners with two equivalent O(1)TiFe3 trigonal pyramids, edges with four equivalent O(4)Mg2TiFe2 trigonal bipyramids, and edges with four equivalent O(2)MgTiFe2 trigonal pyramids.