MgTi2Zn2(SiO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(5), one O(8), and one O(9) atom to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Ti(2)O6 octahedra,  an edgeedge with one Si(1)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 62°. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form distorted TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  a faceface with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 33-50°. In the second Ti site, Ti(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 33-50°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a distorted see-saw-like geometry to one O(10), one O(2), one O(4), and one O(7) atom. In the second Zn site, Zn(2) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), one O(6), and one O(9) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 32-53°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 35-46°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted see-saw-like geometry to one Mg(1), one Ti(2), one Zn(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 Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ti(2), one Zn(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Ti(1), one Zn(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Mg(1), one Ti(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Ti(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Ti(1), one Zn(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a T-shaped geometry to one Mg(1), one Ti(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal pyramidal geometry to one Mg(1), one Ti(1), one Ti(2), and one Zn(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Ti(1), one Ti(2), and one Zn(1) atom.
MgTi2Zn2(SiO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(5), one O(8), and one O(9) atom to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Ti(2)O6 octahedra,  an edgeedge with one Si(1)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 62°. The Mg(1)-O(1) bond length is 2.12 Å. The Mg(1)-O(4) bond length is 2.05 Å. The Mg(1)-O(5) bond length is 2.02 Å. The Mg(1)-O(8) bond length is 2.05 Å. The Mg(1)-O(9) bond length is 2.14 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form distorted TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  a faceface with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 33-50°. The Ti(1)-O(10) bond length is 1.93 Å. The Ti(1)-O(2) bond length is 2.03 Å. The Ti(1)-O(4) bond length is 2.29 Å. The Ti(1)-O(5) bond length is 2.18 Å. The Ti(1)-O(7) bond length is 2.11 Å. The Ti(1)-O(9) bond length is 2.00 Å. In the second Ti site, Ti(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 33-50°. The Ti(2)-O(1) bond length is 2.15 Å. The Ti(2)-O(10) bond length is 1.95 Å. The Ti(2)-O(3) bond length is 2.14 Å. The Ti(2)-O(6) bond length is 2.07 Å. The Ti(2)-O(8) bond length is 2.10 Å. The Ti(2)-O(9) bond length is 2.04 Å. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a distorted see-saw-like geometry to one O(10), one O(2), one O(4), and one O(7) atom. The Zn(1)-O(10) bond length is 1.92 Å. The Zn(1)-O(2) bond length is 2.07 Å. The Zn(1)-O(4) bond length is 2.11 Å. The Zn(1)-O(7) bond length is 1.97 Å. In the second Zn site, Zn(2) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), one O(6), and one O(9) atom. The Zn(2)-O(1) bond length is 2.16 Å. The Zn(2)-O(3) bond length is 2.04 Å. The Zn(2)-O(6) bond length is 2.00 Å. The Zn(2)-O(9) bond length is 1.98 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 32-53°. The Si(1)-O(1) bond length is 1.69 Å. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(7) bond length is 1.64 Å. The Si(1)-O(8) bond length is 1.64 Å. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 35-46°. The Si(2)-O(3) bond length is 1.67 Å. The Si(2)-O(4) bond length is 1.65 Å. The Si(2)-O(5) bond length is 1.62 Å. The Si(2)-O(6) bond length is 1.66 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted see-saw-like geometry to one Mg(1), one Ti(2), one Zn(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 Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ti(2), one Zn(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Ti(1), one Zn(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Mg(1), one Ti(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Ti(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Ti(1), one Zn(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a T-shaped geometry to one Mg(1), one Ti(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal pyramidal geometry to one Mg(1), one Ti(1), one Ti(2), and one Zn(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Ti(1), one Ti(2), and one Zn(1) atom.