MoP2O7 crystallizes in the monoclinic C2/c space group. Mo(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form MoO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mo(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-49°. In the second P site, P(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Mo(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-47°. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1) atom. In the second O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mo(1) and one P(2) atom. In the third O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Mo(1) and one P(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(2) atom. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(2) atom. In the sixth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Mo(1) and one P(1) atom. In the seventh O site, O(4) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom.
MoP2O7 crystallizes in the monoclinic C2/c space group. Mo(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form MoO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. The Mo(1)-O(1) bond length is 2.06 Å. The Mo(1)-O(2) bond length is 2.08 Å. The Mo(1)-O(3) bond length is 2.02 Å. The Mo(1)-O(5) bond length is 2.09 Å. The Mo(1)-O(6) bond length is 2.05 Å. The Mo(1)-O(7) bond length is 2.08 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mo(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-49°. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.62 Å. The P(1)-O(5) bond length is 1.52 Å. The P(1)-O(7) bond length is 1.52 Å. In the second P site, P(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Mo(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-47°. The P(2)-O(1) bond length is 1.52 Å. The P(2)-O(2) bond length is 1.53 Å. The P(2)-O(4) bond length is 1.62 Å. The P(2)-O(6) bond length is 1.54 Å. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1) atom. In the second O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mo(1) and one P(2) atom. In the third O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Mo(1) and one P(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(2) atom. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(2) atom. In the sixth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Mo(1) and one P(1) atom. In the seventh O site, O(4) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom.