Li2CoP2O7 crystallizes in the triclinic P1 space group. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted see-saw-like geometry to one O(10), one O(15), one O(17), and one O(5) atom. In the second Li site, Li(2) is bonded in a distorted see-saw-like geometry to one O(16), one O(18), one O(6), and one O(9) atom. In the third Li site, Li(3) is bonded in a distorted see-saw-like geometry to one O(11), one O(13), one O(19), and one O(7) atom. In the fourth Li site, Li(4) is bonded in a distorted see-saw-like geometry to one O(12), one O(14), one O(20), and one O(8) atom. In the fifth Li site, Li(5) is bonded in a rectangular see-saw-like geometry to one O(17), one O(21), one O(4), and one O(5) atom. In the sixth Li site, Li(6) is bonded in a rectangular see-saw-like geometry to one O(18), one O(22), one O(3), and one O(6) atom. In the seventh Li site, Li(7) is bonded in a rectangular see-saw-like geometry to one O(19), one O(2), one O(24), and one O(7) atom. In the eighth Li site, Li(8) is bonded in a rectangular see-saw-like geometry to one O(1), one O(20), one O(23), and one O(8) atom. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(12), one O(14), one O(18), one O(2), one O(22), and one O(6) atom to form distorted CoO6 octahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and corners with two equivalent P(8)O4 tetrahedra. In the second Co site, Co(2) is bonded to one O(16), one O(19), one O(24), one O(4), one O(7), and one O(9) atom to form CoO6 octahedra that share  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(6)O4 tetrahedra. In the third Co site, Co(3) is bonded to one O(1), one O(11), one O(13), one O(17), one O(21), and one O(5) atom to form distorted CoO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(7)O4 tetrahedra. In the fourth Co site, Co(4) is bonded to one O(10), one O(15), one O(20), one O(23), one O(3), and one O(8) atom to form CoO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent P(5)O4 tetrahedra. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(13), one O(19), one O(25), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Co(3)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-50°. In the second P site, P(2) is bonded to one O(10), one O(14), one O(20), and one O(26) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, and  a cornercorner with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. In the third P site, P(3) is bonded to one O(11), one O(15), one O(17), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Co(4)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, and  a cornercorner with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-50°. In the fourth P site, P(4) is bonded to one O(12), one O(16), one O(18), and one O(28) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and  a cornercorner with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. In the fifth P site, P(5) is bonded to one O(23), one O(27), one O(3), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. In the sixth P site, P(6) is bonded to one O(24), one O(28), one O(4), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Co(3)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. In the seventh P site, P(7) is bonded to one O(1), one O(21), one O(25), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Co(4)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. In the eighth P site, P(8) is bonded to one O(2), one O(22), one O(26), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(8), one Co(3), and one P(7) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(7), one Co(1), and one P(8) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(6), one Co(4), and one P(5) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(5), one Co(2), and one P(6) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(5), one Co(3), and one P(6) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Li(2), one Li(6), one Co(1), and one P(5) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Li(7), one Co(2), and one P(8) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Li(4), one Li(8), one Co(4), and one P(7) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Li(2), one Co(2), and one P(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(1), one Co(4), and one P(2) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Li(3), one Co(3), and one P(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Li(4), one Co(1), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(3), one Co(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Li(4), one Co(1), and one P(2) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Li(1), one Co(4), and one P(3) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Li(2), one Co(2), and one P(4) atom. In the seventeenth O site, O(17) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(5), one Co(3), and one P(3) atom. In the eighteenth O site, O(18) is bonded in a distorted rectangular see-saw-like geometry to one Li(2), one Li(6), one Co(1), and one P(4) atom. In the nineteenth O site, O(19) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Li(7), one Co(2), and one P(1) atom. In the twentieth O site, O(20) is bonded in a distorted rectangular see-saw-like geometry to one Li(4), one Li(8), one Co(4), and one P(2) atom. In the twenty-first O site, O(21) is bonded in a 3-coordinate geometry to one Li(5), one Co(3), and one P(7) atom. In the twenty-second O site, O(22) is bonded in a 3-coordinate geometry to one Li(6), one Co(1), and one P(8) atom. In the twenty-third O site, O(23) is bonded in a 3-coordinate geometry to one Li(8), one Co(4), and one P(5) atom. In the twenty-fourth O site, O(24) is bonded in a 3-coordinate geometry to one Li(7), one Co(2), and one P(6) atom. In the twenty-fifth O site, O(25) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(7) atom. In the twenty-sixth O site, O(26) is bonded in a distorted bent 150 degrees geometry to one P(2) and one P(8) atom. In the twenty-seventh O site, O(27) is bonded in a distorted bent 150 degrees geometry to one P(3) and one P(5) atom. In the twenty-eighth O site, O(28) is bonded in a distorted bent 150 degrees geometry to one P(4) and one P(6) atom.
Li2CoP2O7 crystallizes in the triclinic P1 space group. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted see-saw-like geometry to one O(10), one O(15), one O(17), and one O(5) atom. The Li(1)-O(10) bond length is 1.96 Å. The Li(1)-O(15) bond length is 1.93 Å. The Li(1)-O(17) bond length is 1.94 Å. The Li(1)-O(5) bond length is 2.13 Å. In the second Li site, Li(2) is bonded in a distorted see-saw-like geometry to one O(16), one O(18), one O(6), and one O(9) atom. The Li(2)-O(16) bond length is 1.93 Å. The Li(2)-O(18) bond length is 1.95 Å. The Li(2)-O(6) bond length is 2.12 Å. The Li(2)-O(9) bond length is 1.96 Å. In the third Li site, Li(3) is bonded in a distorted see-saw-like geometry to one O(11), one O(13), one O(19), and one O(7) atom. The Li(3)-O(11) bond length is 1.95 Å. The Li(3)-O(13) bond length is 1.93 Å. The Li(3)-O(19) bond length is 1.95 Å. The Li(3)-O(7) bond length is 2.11 Å. In the fourth Li site, Li(4) is bonded in a distorted see-saw-like geometry to one O(12), one O(14), one O(20), and one O(8) atom. The Li(4)-O(12) bond length is 1.96 Å. The Li(4)-O(14) bond length is 1.93 Å. The Li(4)-O(20) bond length is 1.95 Å. The Li(4)-O(8) bond length is 2.10 Å. In the fifth Li site, Li(5) is bonded in a rectangular see-saw-like geometry to one O(17), one O(21), one O(4), and one O(5) atom. The Li(5)-O(17) bond length is 2.03 Å. The Li(5)-O(21) bond length is 1.95 Å. The Li(5)-O(4) bond length is 1.97 Å. The Li(5)-O(5) bond length is 2.21 Å. In the sixth Li site, Li(6) is bonded in a rectangular see-saw-like geometry to one O(18), one O(22), one O(3), and one O(6) atom. The Li(6)-O(18) bond length is 2.02 Å. The Li(6)-O(22) bond length is 1.95 Å. The Li(6)-O(3) bond length is 1.97 Å. The Li(6)-O(6) bond length is 2.26 Å. In the seventh Li site, Li(7) is bonded in a rectangular see-saw-like geometry to one O(19), one O(2), one O(24), and one O(7) atom. The Li(7)-O(19) bond length is 2.02 Å. The Li(7)-O(2) bond length is 1.98 Å. The Li(7)-O(24) bond length is 1.95 Å. The Li(7)-O(7) bond length is 2.22 Å. In the eighth Li site, Li(8) is bonded in a rectangular see-saw-like geometry to one O(1), one O(20), one O(23), and one O(8) atom. The Li(8)-O(1) bond length is 1.97 Å. The Li(8)-O(20) bond length is 2.02 Å. The Li(8)-O(23) bond length is 1.95 Å. The Li(8)-O(8) bond length is 2.24 Å. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(12), one O(14), one O(18), one O(2), one O(22), and one O(6) atom to form distorted CoO6 octahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and corners with two equivalent P(8)O4 tetrahedra. The Co(1)-O(12) bond length is 2.09 Å. The Co(1)-O(14) bond length is 2.05 Å. The Co(1)-O(18) bond length is 2.28 Å. The Co(1)-O(2) bond length is 2.17 Å. The Co(1)-O(22) bond length is 2.09 Å. The Co(1)-O(6) bond length is 2.15 Å. In the second Co site, Co(2) is bonded to one O(16), one O(19), one O(24), one O(4), one O(7), and one O(9) atom to form CoO6 octahedra that share  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(6)O4 tetrahedra. The Co(2)-O(16) bond length is 2.06 Å. The Co(2)-O(19) bond length is 2.28 Å. The Co(2)-O(24) bond length is 2.08 Å. The Co(2)-O(4) bond length is 2.18 Å. The Co(2)-O(7) bond length is 2.15 Å. The Co(2)-O(9) bond length is 2.09 Å. In the third Co site, Co(3) is bonded to one O(1), one O(11), one O(13), one O(17), one O(21), and one O(5) atom to form distorted CoO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(7)O4 tetrahedra. The Co(3)-O(1) bond length is 2.16 Å. The Co(3)-O(11) bond length is 2.09 Å. The Co(3)-O(13) bond length is 2.05 Å. The Co(3)-O(17) bond length is 2.30 Å. The Co(3)-O(21) bond length is 2.10 Å. The Co(3)-O(5) bond length is 2.14 Å. In the fourth Co site, Co(4) is bonded to one O(10), one O(15), one O(20), one O(23), one O(3), and one O(8) atom to form CoO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent P(5)O4 tetrahedra. The Co(4)-O(10) bond length is 2.10 Å. The Co(4)-O(15) bond length is 2.05 Å. The Co(4)-O(20) bond length is 2.27 Å. The Co(4)-O(23) bond length is 2.09 Å. The Co(4)-O(3) bond length is 2.16 Å. The Co(4)-O(8) bond length is 2.15 Å. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(13), one O(19), one O(25), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Co(3)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-50°. The P(1)-O(13) bond length is 1.53 Å. The P(1)-O(19) bond length is 1.54 Å. The P(1)-O(25) bond length is 1.62 Å. The P(1)-O(9) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(10), one O(14), one O(20), and one O(26) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, and  a cornercorner with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. The P(2)-O(10) bond length is 1.53 Å. The P(2)-O(14) bond length is 1.53 Å. The P(2)-O(20) bond length is 1.54 Å. The P(2)-O(26) bond length is 1.62 Å. In the third P site, P(3) is bonded to one O(11), one O(15), one O(17), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Co(4)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, and  a cornercorner with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-50°. The P(3)-O(11) bond length is 1.53 Å. The P(3)-O(15) bond length is 1.53 Å. The P(3)-O(17) bond length is 1.53 Å. The P(3)-O(27) bond length is 1.63 Å. In the fourth P site, P(4) is bonded to one O(12), one O(16), one O(18), and one O(28) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and  a cornercorner with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. The P(4)-O(12) bond length is 1.53 Å. The P(4)-O(16) bond length is 1.53 Å. The P(4)-O(18) bond length is 1.54 Å. The P(4)-O(28) bond length is 1.63 Å. In the fifth P site, P(5) is bonded to one O(23), one O(27), one O(3), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. The P(5)-O(23) bond length is 1.53 Å. The P(5)-O(27) bond length is 1.63 Å. The P(5)-O(3) bond length is 1.53 Å. The P(5)-O(6) bond length is 1.54 Å. In the sixth P site, P(6) is bonded to one O(24), one O(28), one O(4), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Co(3)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. The P(6)-O(24) bond length is 1.53 Å. The P(6)-O(28) bond length is 1.62 Å. The P(6)-O(4) bond length is 1.53 Å. The P(6)-O(5) bond length is 1.54 Å. In the seventh P site, P(7) is bonded to one O(1), one O(21), one O(25), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Co(4)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. The P(7)-O(1) bond length is 1.53 Å. The P(7)-O(21) bond length is 1.53 Å. The P(7)-O(25) bond length is 1.63 Å. The P(7)-O(8) bond length is 1.54 Å. In the eighth P site, P(8) is bonded to one O(2), one O(22), one O(26), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-52°. The P(8)-O(2) bond length is 1.53 Å. The P(8)-O(22) bond length is 1.53 Å. The P(8)-O(26) bond length is 1.62 Å. The P(8)-O(7) bond length is 1.54 Å. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(8), one Co(3), and one P(7) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(7), one Co(1), and one P(8) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(6), one Co(4), and one P(5) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(5), one Co(2), and one P(6) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(5), one Co(3), and one P(6) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Li(2), one Li(6), one Co(1), and one P(5) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Li(7), one Co(2), and one P(8) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Li(4), one Li(8), one Co(4), and one P(7) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Li(2), one Co(2), and one P(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(1), one Co(4), and one P(2) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Li(3), one Co(3), and one P(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Li(4), one Co(1), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(3), one Co(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Li(4), one Co(1), and one P(2) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Li(1), one Co(4), and one P(3) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Li(2), one Co(2), and one P(4) atom. In the seventeenth O site, O(17) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(5), one Co(3), and one P(3) atom. In the eighteenth O site, O(18) is bonded in a distorted rectangular see-saw-like geometry to one Li(2), one Li(6), one Co(1), and one P(4) atom. In the nineteenth O site, O(19) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Li(7), one Co(2), and one P(1) atom. In the twentieth O site, O(20) is bonded in a distorted rectangular see-saw-like geometry to one Li(4), one Li(8), one Co(4), and one P(2) atom. In the twenty-first O site, O(21) is bonded in a 3-coordinate geometry to one Li(5), one Co(3), and one P(7) atom. In the twenty-second O site, O(22) is bonded in a 3-coordinate geometry to one Li(6), one Co(1), and one P(8) atom. In the twenty-third O site, O(23) is bonded in a 3-coordinate geometry to one Li(8), one Co(4), and one P(5) atom. In the twenty-fourth O site, O(24) is bonded in a 3-coordinate geometry to one Li(7), one Co(2), and one P(6) atom. In the twenty-fifth O site, O(25) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(7) atom. In the twenty-sixth O site, O(26) is bonded in a distorted bent 150 degrees geometry to one P(2) and one P(8) atom. In the twenty-seventh O site, O(27) is bonded in a distorted bent 150 degrees geometry to one P(3) and one P(5) atom. In the twenty-eighth O site, O(28) is bonded in a distorted bent 150 degrees geometry to one P(4) and one P(6) atom.