LiMnP2O7 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and  an edgeedge with one Mn(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 67-69°. In the second Li site, Li(2) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(11), one O(6), and one O(8) atom. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), one O(5), one O(7), and one O(9) atom to form distorted MnO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to one O(10), one O(12), one O(14), one O(4), one O(6), and one O(8) atom to form distorted MnO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(12), one O(13), and one O(3) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid,  a cornercorner with one P(2)O4 tetrahedra, and corners with two equivalent Li(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. In the second P site, P(2) is bonded to one O(10), one O(13), one O(2), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. In the third P site, P(3) is bonded to one O(1), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid,  a cornercorner with one Li(1)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. In the fourth P site, P(4) is bonded to one O(1), one O(14), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid,  a cornercorner with one Li(1)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-48°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one P(3) and one P(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Mn(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 Mn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(2), and one P(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Li(1), one Mn(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(2) atom. In the eleventh O site, O(11) is bonded in a distorted water-like geometry to one Li(2) and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Mn(2), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(4) atom.
LiMnP2O7 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and  an edgeedge with one Mn(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 67-69°. The Li(1)-O(12) bond length is 2.00 Å. The Li(1)-O(3) bond length is 1.97 Å. The Li(1)-O(4) bond length is 1.97 Å. The Li(1)-O(7) bond length is 2.01 Å. In the second Li site, Li(2) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(11), one O(6), and one O(8) atom. The Li(2)-O(10) bond length is 2.24 Å. The Li(2)-O(11) bond length is 2.00 Å. The Li(2)-O(6) bond length is 2.19 Å. The Li(2)-O(8) bond length is 1.95 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), one O(5), one O(7), and one O(9) atom to form distorted MnO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. The Mn(1)-O(2) bond length is 2.07 Å. The Mn(1)-O(3) bond length is 2.00 Å. The Mn(1)-O(5) bond length is 1.97 Å. The Mn(1)-O(7) bond length is 1.95 Å. The Mn(1)-O(9) bond length is 1.91 Å. In the second Mn site, Mn(2) is bonded to one O(10), one O(12), one O(14), one O(4), one O(6), and one O(8) atom to form distorted MnO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. The Mn(2)-O(10) bond length is 1.94 Å. The Mn(2)-O(12) bond length is 1.96 Å. The Mn(2)-O(14) bond length is 1.94 Å. The Mn(2)-O(4) bond length is 2.23 Å. The Mn(2)-O(6) bond length is 1.97 Å. The Mn(2)-O(8) bond length is 2.51 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(12), one O(13), and one O(3) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid,  a cornercorner with one P(2)O4 tetrahedra, and corners with two equivalent Li(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. The P(1)-O(11) bond length is 1.50 Å. The P(1)-O(12) bond length is 1.55 Å. The P(1)-O(13) bond length is 1.62 Å. The P(1)-O(3) bond length is 1.55 Å. In the second P site, P(2) is bonded to one O(10), one O(13), one O(2), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. The P(2)-O(10) bond length is 1.56 Å. The P(2)-O(13) bond length is 1.62 Å. The P(2)-O(2) bond length is 1.50 Å. The P(2)-O(9) bond length is 1.54 Å. In the third P site, P(3) is bonded to one O(1), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid,  a cornercorner with one Li(1)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. The P(3)-O(1) bond length is 1.62 Å. The P(3)-O(6) bond length is 1.55 Å. The P(3)-O(7) bond length is 1.54 Å. The P(3)-O(8) bond length is 1.51 Å. In the fourth P site, P(4) is bonded to one O(1), one O(14), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid,  a cornercorner with one Li(1)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-48°. The P(4)-O(1) bond length is 1.62 Å. The P(4)-O(14) bond length is 1.54 Å. The P(4)-O(4) bond length is 1.53 Å. The P(4)-O(5) bond length is 1.54 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one P(3) and one P(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Mn(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 Mn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(2), and one P(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Li(1), one Mn(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(2) atom. In the eleventh O site, O(11) is bonded in a distorted water-like geometry to one Li(2) and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Mn(2), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(4) atom.