Li2FeCPO7 crystallizes in the triclinic P1 space group. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(10), one O(17), one O(21), and one O(9) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, and corners with two equivalent P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-72°. In the second Li site, Li(2) is bonded to one O(11), one O(14), one O(15), and one O(26) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and corners with two equivalent P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 61-73°. In the third Li site, Li(3) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(14), one O(22), and one O(6) atom. In the fourth Li site, Li(4) is bonded in a rectangular see-saw-like geometry to one O(16), one O(20), one O(27), and one O(5) atom. In the fifth Li site, Li(5) is bonded in a 5-coordinate geometry to one O(13), one O(18), one O(19), one O(23), and one O(7) atom. In the sixth Li site, Li(6) is bonded to one O(12), one O(13), one O(16), and one O(3) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 63-74°. In the seventh Li site, Li(7) is bonded in a distorted see-saw-like geometry to one O(11), one O(24), one O(28), and one O(4) atom. In the eighth Li site, Li(8) is bonded to one O(1), one O(18), one O(20), and one O(8) atom to form distorted LiO4 trigonal pyramids that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(13), one O(23), one O(3), one O(4), one O(7), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(15), one O(20), one O(27), one O(5), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra,  a cornercorner with one Li(8)O4 trigonal pyramid, and  an edgeedge with one Li(8)O4 trigonal pyramid. In the third Fe site, Fe(3) is bonded to one O(12), one O(17), one O(2), one O(21), one O(24), and one O(28) atom to form FeO6 octahedra that share  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. In the fourth Fe site, Fe(4) is bonded to one O(14), one O(19), one O(22), one O(25), one O(26), and one O(6) atom to form FeO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(10), and one O(20) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(11), one O(13), and one O(4) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(14), one O(16), and one O(25) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(17), one O(18), and one O(28) atom. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(2), one O(3), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, and corners with two equivalent Li(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-53°. In the second P site, P(2) is bonded to one O(19), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and  a cornercorner with one Li(8)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 45-52°. In the third P site, P(3) is bonded to one O(21), one O(22), one O(23), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Li(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the fourth P site, P(4) is bonded to one O(15), one O(24), one O(26), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, and corners with two equivalent Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(8), one Fe(2), and one C(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Fe(3) and one P(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(6), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Li(7), one Fe(1), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Li(4), one Fe(2), and one P(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(3), one Fe(4), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Li(5), one Fe(1), and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Li(8), one Fe(2), and one P(2) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one P(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(3), and one C(1) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Li(2), one Li(7), and one C(2) atom. In the twelfth O site, O(12) is bonded in a trigonal planar geometry to one Li(6), one Fe(3), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Li(5), one Li(6), one Fe(1), and one C(2) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal pyramidal geometry to one Li(2), one Li(3), one Fe(4), and one C(3) atom. In the fifteenth O site, O(15) is bonded in a trigonal planar geometry to one Li(2), one Fe(2), and one P(4) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Li(4), one Li(6), and one C(3) atom. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Li(1), one Fe(3), and one C(4) atom. In the eighteenth O site, O(18) is bonded in a trigonal planar geometry to one Li(5), one Li(8), and one C(4) atom. In the nineteenth O site, O(19) is bonded in a 3-coordinate geometry to one Li(5), one Fe(4), and one P(2) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal pyramidal geometry to one Li(4), one Li(8), one Fe(2), and one C(1) atom. In the twenty-first O site, O(21) is bonded in a trigonal planar geometry to one Li(1), one Fe(3), and one P(3) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Li(3), one Fe(4), and one P(3) atom. In the twenty-third O site, O(23) is bonded in a trigonal planar geometry to one Li(5), one Fe(1), and one P(3) atom. In the twenty-fourth O site, O(24) is bonded in a distorted trigonal planar geometry to one Li(7), one Fe(3), and one P(4) atom. In the twenty-fifth O site, O(25) is bonded in a distorted L-shaped geometry to one Fe(4) and one C(3) atom. In the twenty-sixth O site, O(26) is bonded in a trigonal planar geometry to one Li(2), one Fe(4), and one P(4) atom. In the twenty-seventh O site, O(27) is bonded in a trigonal planar geometry to one Li(4), one Fe(2), and one P(4) atom. In the twenty-eighth O site, O(28) is bonded in a 3-coordinate geometry to one Li(7), one Fe(3), and one C(4) atom.
Li2FeCPO7 crystallizes in the triclinic P1 space group. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(10), one O(17), one O(21), and one O(9) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, and corners with two equivalent P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-72°. The Li(1)-O(10) bond length is 1.96 Å. The Li(1)-O(17) bond length is 1.91 Å. The Li(1)-O(21) bond length is 1.96 Å. The Li(1)-O(9) bond length is 2.16 Å. In the second Li site, Li(2) is bonded to one O(11), one O(14), one O(15), and one O(26) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and corners with two equivalent P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 61-73°. The Li(2)-O(11) bond length is 1.97 Å. The Li(2)-O(14) bond length is 2.10 Å. The Li(2)-O(15) bond length is 2.11 Å. The Li(2)-O(26) bond length is 2.07 Å. In the third Li site, Li(3) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(14), one O(22), and one O(6) atom. The Li(3)-O(10) bond length is 1.93 Å. The Li(3)-O(14) bond length is 2.02 Å. The Li(3)-O(22) bond length is 2.07 Å. The Li(3)-O(6) bond length is 2.00 Å. In the fourth Li site, Li(4) is bonded in a rectangular see-saw-like geometry to one O(16), one O(20), one O(27), and one O(5) atom. The Li(4)-O(16) bond length is 1.94 Å. The Li(4)-O(20) bond length is 2.04 Å. The Li(4)-O(27) bond length is 2.02 Å. The Li(4)-O(5) bond length is 2.04 Å. In the fifth Li site, Li(5) is bonded in a 5-coordinate geometry to one O(13), one O(18), one O(19), one O(23), and one O(7) atom. The Li(5)-O(13) bond length is 2.52 Å. The Li(5)-O(18) bond length is 1.96 Å. The Li(5)-O(19) bond length is 2.27 Å. The Li(5)-O(23) bond length is 2.03 Å. The Li(5)-O(7) bond length is 2.05 Å. In the sixth Li site, Li(6) is bonded to one O(12), one O(13), one O(16), and one O(3) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 63-74°. The Li(6)-O(12) bond length is 2.17 Å. The Li(6)-O(13) bond length is 2.06 Å. The Li(6)-O(16) bond length is 1.96 Å. The Li(6)-O(3) bond length is 1.99 Å. In the seventh Li site, Li(7) is bonded in a distorted see-saw-like geometry to one O(11), one O(24), one O(28), and one O(4) atom. The Li(7)-O(11) bond length is 2.15 Å. The Li(7)-O(24) bond length is 1.95 Å. The Li(7)-O(28) bond length is 2.17 Å. The Li(7)-O(4) bond length is 1.98 Å. In the eighth Li site, Li(8) is bonded to one O(1), one O(18), one O(20), and one O(8) atom to form distorted LiO4 trigonal pyramids that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. The Li(8)-O(1) bond length is 2.06 Å. The Li(8)-O(18) bond length is 1.95 Å. The Li(8)-O(20) bond length is 2.06 Å. The Li(8)-O(8) bond length is 2.10 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(13), one O(23), one O(3), one O(4), one O(7), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. The Fe(1)-O(13) bond length is 2.09 Å. The Fe(1)-O(23) bond length is 2.01 Å. The Fe(1)-O(3) bond length is 2.02 Å. The Fe(1)-O(4) bond length is 2.17 Å. The Fe(1)-O(7) bond length is 2.04 Å. The Fe(1)-O(9) bond length is 2.00 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(15), one O(20), one O(27), one O(5), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra,  a cornercorner with one Li(8)O4 trigonal pyramid, and  an edgeedge with one Li(8)O4 trigonal pyramid. The Fe(2)-O(1) bond length is 2.13 Å. The Fe(2)-O(15) bond length is 2.00 Å. The Fe(2)-O(20) bond length is 2.10 Å. The Fe(2)-O(27) bond length is 2.00 Å. The Fe(2)-O(5) bond length is 2.02 Å. The Fe(2)-O(8) bond length is 2.04 Å. In the third Fe site, Fe(3) is bonded to one O(12), one O(17), one O(2), one O(21), one O(24), and one O(28) atom to form FeO6 octahedra that share  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. The Fe(3)-O(12) bond length is 2.02 Å. The Fe(3)-O(17) bond length is 2.17 Å. The Fe(3)-O(2) bond length is 1.96 Å. The Fe(3)-O(21) bond length is 2.09 Å. The Fe(3)-O(24) bond length is 2.05 Å. The Fe(3)-O(28) bond length is 2.05 Å. In the fourth Fe site, Fe(4) is bonded to one O(14), one O(19), one O(22), one O(25), one O(26), and one O(6) atom to form FeO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Fe(4)-O(14) bond length is 2.11 Å. The Fe(4)-O(19) bond length is 2.01 Å. The Fe(4)-O(22) bond length is 2.04 Å. The Fe(4)-O(25) bond length is 2.10 Å. The Fe(4)-O(26) bond length is 2.05 Å. The Fe(4)-O(6) bond length is 1.98 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(10), and one O(20) atom. The C(1)-O(1) bond length is 1.30 Å. The C(1)-O(10) bond length is 1.26 Å. The C(1)-O(20) bond length is 1.33 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(11), one O(13), and one O(4) atom. The C(2)-O(11) bond length is 1.26 Å. The C(2)-O(13) bond length is 1.33 Å. The C(2)-O(4) bond length is 1.31 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(14), one O(16), and one O(25) atom. The C(3)-O(14) bond length is 1.34 Å. The C(3)-O(16) bond length is 1.27 Å. The C(3)-O(25) bond length is 1.30 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(17), one O(18), and one O(28) atom. The C(4)-O(17) bond length is 1.30 Å. The C(4)-O(18) bond length is 1.28 Å. The C(4)-O(28) bond length is 1.32 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(2), one O(3), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, and corners with two equivalent Li(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-53°. The P(1)-O(12) bond length is 1.57 Å. The P(1)-O(2) bond length is 1.54 Å. The P(1)-O(3) bond length is 1.56 Å. The P(1)-O(5) bond length is 1.56 Å. In the second P site, P(2) is bonded to one O(19), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and  a cornercorner with one Li(8)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 45-52°. The P(2)-O(19) bond length is 1.56 Å. The P(2)-O(6) bond length is 1.56 Å. The P(2)-O(7) bond length is 1.55 Å. The P(2)-O(8) bond length is 1.54 Å. In the third P site, P(3) is bonded to one O(21), one O(22), one O(23), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Li(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-51°. The P(3)-O(21) bond length is 1.54 Å. The P(3)-O(22) bond length is 1.55 Å. The P(3)-O(23) bond length is 1.57 Å. The P(3)-O(9) bond length is 1.57 Å. In the fourth P site, P(4) is bonded to one O(15), one O(24), one O(26), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, and corners with two equivalent Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-54°. The P(4)-O(15) bond length is 1.56 Å. The P(4)-O(24) bond length is 1.54 Å. The P(4)-O(26) bond length is 1.55 Å. The P(4)-O(27) bond length is 1.56 Å. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(8), one Fe(2), and one C(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Fe(3) and one P(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(6), one Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Li(7), one Fe(1), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Li(4), one Fe(2), and one P(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(3), one Fe(4), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Li(5), one Fe(1), and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Li(8), one Fe(2), and one P(2) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one P(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Li(1), one Li(3), and one C(1) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Li(2), one Li(7), and one C(2) atom. In the twelfth O site, O(12) is bonded in a trigonal planar geometry to one Li(6), one Fe(3), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Li(5), one Li(6), one Fe(1), and one C(2) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal pyramidal geometry to one Li(2), one Li(3), one Fe(4), and one C(3) atom. In the fifteenth O site, O(15) is bonded in a trigonal planar geometry to one Li(2), one Fe(2), and one P(4) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Li(4), one Li(6), and one C(3) atom. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Li(1), one Fe(3), and one C(4) atom. In the eighteenth O site, O(18) is bonded in a trigonal planar geometry to one Li(5), one Li(8), and one C(4) atom. In the nineteenth O site, O(19) is bonded in a 3-coordinate geometry to one Li(5), one Fe(4), and one P(2) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal pyramidal geometry to one Li(4), one Li(8), one Fe(2), and one C(1) atom. In the twenty-first O site, O(21) is bonded in a trigonal planar geometry to one Li(1), one Fe(3), and one P(3) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Li(3), one Fe(4), and one P(3) atom. In the twenty-third O site, O(23) is bonded in a trigonal planar geometry to one Li(5), one Fe(1), and one P(3) atom. In the twenty-fourth O site, O(24) is bonded in a distorted trigonal planar geometry to one Li(7), one Fe(3), and one P(4) atom. In the twenty-fifth O site, O(25) is bonded in a distorted L-shaped geometry to one Fe(4) and one C(3) atom. In the twenty-sixth O site, O(26) is bonded in a trigonal planar geometry to one Li(2), one Fe(4), and one P(4) atom. In the twenty-seventh O site, O(27) is bonded in a trigonal planar geometry to one Li(4), one Fe(2), and one P(4) atom. In the twenty-eighth O site, O(28) is bonded in a 3-coordinate geometry to one Li(7), one Fe(3), and one C(4) atom.