MgTi2Al4O10 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form distorted MgO6 octahedra that share corners with two equivalent Al(1)O5 trigonal bipyramids, corners with four equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Al(1)O5 trigonal bipyramids. Ti(1) is bonded to one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form distorted TiO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Ti(1)O5 trigonal bipyramids, corners with three equivalent Al(1)O5 trigonal bipyramids, corners with three equivalent Al(2)O5 trigonal bipyramids, and  an edgeedge with one Al(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 64°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(4), and three equivalent O(1) atoms to form distorted AlO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Al(1)O5 trigonal bipyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Al(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 73°. In the second Al site, Al(2) is bonded to two equivalent O(5) and three equivalent O(2) atoms to form AlO5 trigonal bipyramids that share corners with two equivalent Al(2)O5 trigonal bipyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids,  an edgeedge with one Ti(1)O5 trigonal bipyramid, and edges with three equivalent Al(2)O5 trigonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1) and three equivalent Al(1) atoms to form distorted OMgAl3 tetrahedra that share corners with three equivalent O(1)MgAl3 tetrahedra, corners with three equivalent O(3)Mg2TiAl trigonal pyramids, edges with two equivalent O(1)MgAl3 tetrahedra, and edges with two equivalent O(3)Mg2TiAl trigonal pyramids. In the second O site, O(2) is bonded to one Ti(1) and three equivalent Al(2) atoms to form distorted OTiAl3 trigonal pyramids that share  a cornercorner with one O(3)Mg2TiAl trigonal pyramid, corners with two equivalent O(2)TiAl3 trigonal pyramids, and edges with two equivalent O(2)TiAl3 trigonal pyramids. In the third O site, O(3) is bonded to two equivalent Mg(1), one Ti(1), and one Al(1) atom to form distorted OMg2TiAl trigonal pyramids that share corners with three equivalent O(1)MgAl3 tetrahedra,  a cornercorner with one O(2)TiAl3 trigonal pyramid, corners with four equivalent O(3)Mg2TiAl trigonal pyramids, edges with two equivalent O(1)MgAl3 tetrahedra, and  an edgeedge with one O(3)Mg2TiAl trigonal pyramid. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Ti(1) and one Al(1) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Ti(1) and two equivalent Al(2) atoms.
MgTi2Al4O10 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form distorted MgO6 octahedra that share corners with two equivalent Al(1)O5 trigonal bipyramids, corners with four equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Al(1)O5 trigonal bipyramids. Both Mg(1)-O(1) bond lengths are 2.03 Å. All Mg(1)-O(3) bond lengths are 2.20 Å. Ti(1) is bonded to one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form distorted TiO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Ti(1)O5 trigonal bipyramids, corners with three equivalent Al(1)O5 trigonal bipyramids, corners with three equivalent Al(2)O5 trigonal bipyramids, and  an edgeedge with one Al(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 64°. The Ti(1)-O(2) bond length is 2.28 Å. The Ti(1)-O(3) bond length is 1.99 Å. The Ti(1)-O(5) bond length is 1.93 Å. Both Ti(1)-O(4) bond lengths are 1.98 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(4), and three equivalent O(1) atoms to form distorted AlO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Al(1)O5 trigonal bipyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Al(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 73°. The Al(1)-O(3) bond length is 1.82 Å. The Al(1)-O(4) bond length is 1.81 Å. There are two shorter (1.82 Å) and one longer (1.97 Å) Al(1)-O(1) bond length. In the second Al site, Al(2) is bonded to two equivalent O(5) and three equivalent O(2) atoms to form AlO5 trigonal bipyramids that share corners with two equivalent Al(2)O5 trigonal bipyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids,  an edgeedge with one Ti(1)O5 trigonal bipyramid, and edges with three equivalent Al(2)O5 trigonal bipyramids. Both Al(2)-O(5) bond lengths are 1.86 Å. There are two shorter (1.89 Å) and one longer (2.01 Å) Al(2)-O(2) bond length. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1) and three equivalent Al(1) atoms to form distorted OMgAl3 tetrahedra that share corners with three equivalent O(1)MgAl3 tetrahedra, corners with three equivalent O(3)Mg2TiAl trigonal pyramids, edges with two equivalent O(1)MgAl3 tetrahedra, and edges with two equivalent O(3)Mg2TiAl trigonal pyramids. In the second O site, O(2) is bonded to one Ti(1) and three equivalent Al(2) atoms to form distorted OTiAl3 trigonal pyramids that share  a cornercorner with one O(3)Mg2TiAl trigonal pyramid, corners with two equivalent O(2)TiAl3 trigonal pyramids, and edges with two equivalent O(2)TiAl3 trigonal pyramids. In the third O site, O(3) is bonded to two equivalent Mg(1), one Ti(1), and one Al(1) atom to form distorted OMg2TiAl trigonal pyramids that share corners with three equivalent O(1)MgAl3 tetrahedra,  a cornercorner with one O(2)TiAl3 trigonal pyramid, corners with four equivalent O(3)Mg2TiAl trigonal pyramids, edges with two equivalent O(1)MgAl3 tetrahedra, and  an edgeedge with one O(3)Mg2TiAl trigonal pyramid. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Ti(1) and one Al(1) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Ti(1) and two equivalent Al(2) atoms.