Li2VOP2O7 crystallizes in the monoclinic Cc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted see-saw-like geometry to one O(2), one O(3), one O(6), and one O(8) atom. In the second Li site, Li(2) is bonded to one O(3), one O(5), one O(6), and one O(8) atom to form LiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 62-77°. V(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form VO6 octahedra that share corners with two equivalent Li(2)O4 tetrahedra, 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(1), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra and corners with three equivalent Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 28-62°. In the second P site, P(2) is bonded to one O(2), one O(4), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra and  a cornercorner with one Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one V(1) and one P(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one V(1), and one P(2) atom. In the third O site, O(3) is bonded in a trigonal non-coplanar geometry to one Li(1), one Li(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one V(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(2), one V(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Li(1), one Li(2), one V(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one V(1) and one P(2) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one P(2) atom.
Li2VOP2O7 crystallizes in the monoclinic Cc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted see-saw-like geometry to one O(2), one O(3), one O(6), and one O(8) atom. The Li(1)-O(2) bond length is 2.09 Å. The Li(1)-O(3) bond length is 1.99 Å. The Li(1)-O(6) bond length is 2.35 Å. The Li(1)-O(8) bond length is 2.00 Å. In the second Li site, Li(2) is bonded to one O(3), one O(5), one O(6), and one O(8) atom to form LiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 62-77°. The Li(2)-O(3) bond length is 2.02 Å. The Li(2)-O(5) bond length is 2.15 Å. The Li(2)-O(6) bond length is 2.15 Å. The Li(2)-O(8) bond length is 1.92 Å. V(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form VO6 octahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and corners with three equivalent P(2)O4 tetrahedra. The V(1)-O(1) bond length is 1.84 Å. The V(1)-O(2) bond length is 1.97 Å. The V(1)-O(4) bond length is 1.86 Å. The V(1)-O(5) bond length is 2.04 Å. The V(1)-O(6) bond length is 2.20 Å. The V(1)-O(7) bond length is 1.96 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra and corners with three equivalent Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 28-62°. The P(1)-O(1) bond length is 1.58 Å. The P(1)-O(3) bond length is 1.52 Å. The P(1)-O(5) bond length is 1.56 Å. The P(1)-O(6) bond length is 1.57 Å. In the second P site, P(2) is bonded to one O(2), one O(4), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent V(1)O6 octahedra and  a cornercorner with one Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. The P(2)-O(2) bond length is 1.57 Å. The P(2)-O(4) bond length is 1.58 Å. The P(2)-O(7) bond length is 1.54 Å. The P(2)-O(8) bond length is 1.51 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one V(1) and one P(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one V(1), and one P(2) atom. In the third O site, O(3) is bonded in a trigonal non-coplanar geometry to one Li(1), one Li(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one V(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(2), one V(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Li(1), one Li(2), one V(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one V(1) and one P(2) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one P(2) atom.