Li2MnP2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded in a see-saw-like geometry to one O(14), one O(2), one O(4), and one O(5) atom. In the second Li site, Li(2) is bonded to one O(3), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-74°. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one O(12), one O(7), one O(8), and one O(9) atom. In the fourth Li site, Li(4) is bonded in a see-saw-like geometry to one O(1), one O(10), one O(11), and one O(13) atom. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(10), one O(11), one O(4), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(12), one O(13), one O(14), one O(2), and one O(3) atom to form MnO6 octahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)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(1), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-55°. In the second P site, P(2) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. In the third P site, P(3) is bonded to one O(11), one O(13), one O(8), 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)O6 octahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-56°. In the fourth P site, P(4) is bonded to one O(10), one O(12), one O(14), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-60°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(4), one Mn(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(2), and one P(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Mn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(1), one Li(2), one Mn(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(3), one Mn(1), and one P(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Mn(1), and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Li(3), one P(3), and one P(4) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Li(4), one Mn(1), and one P(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Li(4), one Mn(1), and one P(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Li(3), one Mn(2), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(4), one Mn(2), and one P(3) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Li(1), one Mn(2), and one P(4) atom.
Li2MnP2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded in a see-saw-like geometry to one O(14), one O(2), one O(4), and one O(5) atom. The Li(1)-O(14) bond length is 2.00 Å. The Li(1)-O(2) bond length is 1.96 Å. The Li(1)-O(4) bond length is 1.99 Å. The Li(1)-O(5) bond length is 2.21 Å. In the second Li site, Li(2) is bonded to one O(3), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-74°. The Li(2)-O(3) bond length is 2.01 Å. The Li(2)-O(4) bond length is 2.10 Å. The Li(2)-O(5) bond length is 2.22 Å. The Li(2)-O(8) bond length is 1.95 Å. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one O(12), one O(7), one O(8), and one O(9) atom. The Li(3)-O(12) bond length is 1.98 Å. The Li(3)-O(7) bond length is 1.94 Å. The Li(3)-O(8) bond length is 2.39 Å. The Li(3)-O(9) bond length is 2.03 Å. In the fourth Li site, Li(4) is bonded in a see-saw-like geometry to one O(1), one O(10), one O(11), and one O(13) atom. The Li(4)-O(1) bond length is 2.07 Å. The Li(4)-O(10) bond length is 2.05 Å. The Li(4)-O(11) bond length is 1.98 Å. The Li(4)-O(13) bond length is 1.98 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(10), one O(11), one O(4), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. The Mn(1)-O(10) bond length is 2.15 Å. The Mn(1)-O(11) bond length is 2.16 Å. The Mn(1)-O(4) bond length is 2.27 Å. The Mn(1)-O(5) bond length is 2.24 Å. The Mn(1)-O(7) bond length is 2.21 Å. The Mn(1)-O(8) bond length is 2.29 Å. In the second Mn site, Mn(2) is bonded to one O(1), one O(12), one O(13), one O(14), one O(2), and one O(3) atom to form MnO6 octahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. The Mn(2)-O(1) bond length is 2.23 Å. The Mn(2)-O(12) bond length is 2.30 Å. The Mn(2)-O(13) bond length is 2.11 Å. The Mn(2)-O(14) bond length is 2.24 Å. The Mn(2)-O(2) bond length is 2.11 Å. The Mn(2)-O(3) bond length is 2.24 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-55°. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(3) bond length is 1.53 Å. The P(1)-O(5) bond length is 1.54 Å. The P(1)-O(6) bond length is 1.65 Å. In the second P site, P(2) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. The P(2)-O(2) bond length is 1.52 Å. The P(2)-O(4) bond length is 1.55 Å. The P(2)-O(6) bond length is 1.63 Å. The P(2)-O(7) bond length is 1.53 Å. In the third P site, P(3) is bonded to one O(11), one O(13), one O(8), 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)O6 octahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-56°. The P(3)-O(11) bond length is 1.52 Å. The P(3)-O(13) bond length is 1.53 Å. The P(3)-O(8) bond length is 1.54 Å. The P(3)-O(9) bond length is 1.65 Å. In the fourth P site, P(4) is bonded to one O(10), one O(12), one O(14), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-60°. The P(4)-O(10) bond length is 1.53 Å. The P(4)-O(12) bond length is 1.53 Å. The P(4)-O(14) bond length is 1.54 Å. The P(4)-O(9) bond length is 1.66 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(4), one Mn(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(2), and one P(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(2), one Mn(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Mn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(1), one Li(2), one Mn(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(3), one Mn(1), and one P(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Mn(1), and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Li(3), one P(3), and one P(4) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Li(4), one Mn(1), and one P(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Li(4), one Mn(1), and one P(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Li(3), one Mn(2), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Li(4), one Mn(2), and one P(3) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Li(1), one Mn(2), and one P(4) atom.