LiCrP2O7 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(6) atom to form distorted LiO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with two equivalent Cr(1)O6 octahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(7) atoms to form CrO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, and edges with two equivalent Li(1)O5 trigonal bipyramids. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Cr(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 47-56°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with three equivalent Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with three equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 23-48°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Li(1), one Cr(1), and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Li(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to two equivalent Cr(1) and one P(1) atom.
LiCrP2O7 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(6) atom to form distorted LiO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with two equivalent Cr(1)O6 octahedra. The Li(1)-O(1) bond length is 2.08 Å. The Li(1)-O(2) bond length is 2.36 Å. The Li(1)-O(3) bond length is 2.17 Å. The Li(1)-O(4) bond length is 2.06 Å. The Li(1)-O(6) bond length is 1.92 Å. Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(7) atoms to form CrO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, and edges with two equivalent Li(1)O5 trigonal bipyramids. The Cr(1)-O(1) bond length is 1.98 Å. The Cr(1)-O(2) bond length is 2.03 Å. The Cr(1)-O(3) bond length is 1.96 Å. The Cr(1)-O(4) bond length is 2.00 Å. There is one shorter (2.07 Å) and one longer (2.09 Å) Cr(1)-O(7) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Cr(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 47-56°. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(5) bond length is 1.61 Å. The P(1)-O(6) bond length is 1.48 Å. The P(1)-O(7) bond length is 1.58 Å. In the second P site, P(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with three equivalent Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with three equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 23-48°. The P(2)-O(2) bond length is 1.52 Å. The P(2)-O(3) bond length is 1.54 Å. The P(2)-O(4) bond length is 1.54 Å. The P(2)-O(5) bond length is 1.60 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Li(1), one Cr(1), and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Li(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to two equivalent Cr(1) and one P(1) atom.