MgTiP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Ti(1)O5 square pyramids. Ti(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form distorted TiO5 square pyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Ti(1)O5 square pyramids, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 52-57°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with two equivalent Ti(1)O5 square pyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-55°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Ti(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one P(2) atom.
MgTiP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Ti(1)O5 square pyramids. The Mg(1)-O(1) bond length is 2.22 Å. The Mg(1)-O(3) bond length is 2.22 Å. The Mg(1)-O(5) bond length is 2.11 Å. The Mg(1)-O(7) bond length is 2.18 Å. There is one shorter (2.13 Å) and one longer (2.16 Å) Mg(1)-O(4) bond length. Ti(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form distorted TiO5 square pyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. The Ti(1)-O(1) bond length is 2.18 Å. The Ti(1)-O(2) bond length is 2.00 Å. The Ti(1)-O(3) bond length is 2.16 Å. The Ti(1)-O(5) bond length is 2.47 Å. The Ti(1)-O(7) bond length is 2.12 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Ti(1)O5 square pyramids, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 52-57°. The P(1)-O(1) bond length is 1.54 Å. The P(1)-O(2) bond length is 1.51 Å. The P(1)-O(3) bond length is 1.54 Å. The P(1)-O(6) bond length is 1.61 Å. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with two equivalent Ti(1)O5 square pyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-55°. The P(2)-O(4) bond length is 1.54 Å. The P(2)-O(5) bond length is 1.53 Å. The P(2)-O(6) bond length is 1.60 Å. The P(2)-O(7) bond length is 1.55 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Ti(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one P(2) atom.