TiP2O7 crystallizes in the triclinic P-1 space group. Ti(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms to form distorted TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Ti(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-40°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-60°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom.
TiP2O7 crystallizes in the triclinic P-1 space group. Ti(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms to form distorted TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Ti(1)O6 octahedra. The Ti(1)-O(1) bond length is 1.95 Å. The Ti(1)-O(3) bond length is 1.85 Å. The Ti(1)-O(5) bond length is 1.93 Å. The Ti(1)-O(7) bond length is 1.94 Å. There is one shorter (2.06 Å) and one longer (2.21 Å) Ti(1)-O(6) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-40°. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(4) bond length is 1.59 Å. The P(1)-O(5) bond length is 1.53 Å. The P(1)-O(7) bond length is 1.54 Å. In the second P site, P(2) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ti(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-60°. The P(2)-O(2) bond length is 1.46 Å. The P(2)-O(3) bond length is 1.59 Å. The P(2)-O(4) bond length is 1.61 Å. The P(2)-O(6) bond length is 1.60 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom.