MgTi2(SiO3)4 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(5) and two equivalent O(6) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted TiO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Ti(2)O6 octahedra. In the second Ti site, Ti(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Si(2)O4 tetrahedra, and edges with two equivalent Ti(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 26-58°. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-58°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Si(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ti(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Mg(1), one Ti(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Si(1), and one Si(2) atom.
MgTi2(SiO3)4 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(5) and two equivalent O(6) atoms. Both Mg(1)-O(5) bond lengths are 2.02 Å. Both Mg(1)-O(6) bond lengths are 1.98 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted TiO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Ti(2)O6 octahedra. Both Ti(1)-O(1) bond lengths are 2.23 Å. Both Ti(1)-O(2) bond lengths are 2.05 Å. Both Ti(1)-O(3) bond lengths are 1.97 Å. In the second Ti site, Ti(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Si(2)O4 tetrahedra, and edges with two equivalent Ti(1)O6 octahedra. Both Ti(2)-O(1) bond lengths are 2.05 Å. Both Ti(2)-O(2) bond lengths are 2.08 Å. Both Ti(2)-O(5) bond lengths are 2.12 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 26-58°. The Si(1)-O(1) bond length is 1.65 Å. The Si(1)-O(3) bond length is 1.61 Å. The Si(1)-O(4) bond length is 1.66 Å. The Si(1)-O(6) bond length is 1.69 Å. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-58°. The Si(2)-O(2) bond length is 1.61 Å. The Si(2)-O(4) bond length is 1.64 Å. The Si(2)-O(5) bond length is 1.63 Å. The Si(2)-O(6) bond length is 1.72 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Si(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ti(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Mg(1), one Ti(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Si(1), and one Si(2) atom.