Li2FeCPO7 crystallizes in the monoclinic P2_1/m space group. Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(5), and one O(6) atom. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(6) atoms to form distorted FeO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(5) atom. P(1) is bonded to one O(3), one O(4), and two equivalent O(6) atoms to form PO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-55°. There are six inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), one Fe(1), and one C(1) atom to form distorted edge-sharing OLi2FeC trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Li(1), one Fe(1), and one C(1) atom to form distorted edge-sharing OLi2FeC tetrahedra. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent 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(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Li(1) and one C(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Li(1), one Fe(1), and one P(1) atom.
Li2FeCPO7 crystallizes in the monoclinic P2_1/m space group. Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(5), and one O(6) atom. The Li(1)-O(1) bond length is 2.14 Å. The Li(1)-O(2) bond length is 2.27 Å. The Li(1)-O(3) bond length is 2.26 Å. The Li(1)-O(5) bond length is 2.02 Å. The Li(1)-O(6) bond length is 2.20 Å. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(6) atoms to form distorted FeO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra. The Fe(1)-O(1) bond length is 2.16 Å. The Fe(1)-O(2) bond length is 2.09 Å. The Fe(1)-O(3) bond length is 2.04 Å. The Fe(1)-O(4) bond length is 1.97 Å. Both Fe(1)-O(6) bond lengths are 1.98 Å. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(5) atom. The C(1)-O(1) bond length is 1.31 Å. The C(1)-O(2) bond length is 1.32 Å. The C(1)-O(5) bond length is 1.26 Å. P(1) is bonded to one O(3), one O(4), and two equivalent O(6) atoms to form PO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-55°. The P(1)-O(3) bond length is 1.56 Å. The P(1)-O(4) bond length is 1.56 Å. Both P(1)-O(6) bond lengths are 1.54 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), one Fe(1), and one C(1) atom to form distorted edge-sharing OLi2FeC trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Li(1), one Fe(1), and one C(1) atom to form distorted edge-sharing OLi2FeC tetrahedra. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent 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(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Li(1) and one C(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Li(1), one Fe(1), and one P(1) atom.