LiFe2(PO4)2 crystallizes in the monoclinic Pc space group. Li(1) is bonded to one O(3), one O(5), one O(7), and one O(8) atom to form LiO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. In the second P site, P(2) 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 two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(2) and one P(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(1), one Fe(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(1), one Fe(2), and one P(1) atom.
LiFe2(PO4)2 crystallizes in the monoclinic Pc space group. Li(1) is bonded to one O(3), one O(5), one O(7), and one O(8) atom to form LiO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Li(1)-O(3) bond length is 2.25 Å. The Li(1)-O(5) bond length is 2.08 Å. The Li(1)-O(7) bond length is 2.00 Å. The Li(1)-O(8) bond length is 2.04 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Fe(1)-O(1) bond length is 1.91 Å. The Fe(1)-O(2) bond length is 1.87 Å. The Fe(1)-O(3) bond length is 1.92 Å. The Fe(1)-O(5) bond length is 1.96 Å. In the second Fe site, Fe(2) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Fe(2)-O(4) bond length is 1.97 Å. The Fe(2)-O(6) bond length is 2.03 Å. The Fe(2)-O(7) bond length is 2.04 Å. The Fe(2)-O(8) bond length is 2.08 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. The P(1)-O(2) bond length is 1.56 Å. The P(1)-O(3) bond length is 1.60 Å. The P(1)-O(4) bond length is 1.52 Å. The P(1)-O(8) bond length is 1.54 Å. In the second P site, P(2) 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 two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. The P(2)-O(1) bond length is 1.56 Å. The P(2)-O(5) bond length is 1.59 Å. The P(2)-O(6) bond length is 1.52 Å. The P(2)-O(7) bond length is 1.56 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(2) and one P(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(1), one Fe(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(1), one Fe(2), and one P(1) atom.