LiMn(PO4)2 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form distorted LiO5 trigonal bipyramids that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 70°. Mn(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a cornercorner with one Li(1)O5 trigonal bipyramid, and  an edgeedge with one Li(1)O5 trigonal bipyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and corners with two equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 45-50°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and corners with three equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 40-47°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Li(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Li(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one P(2) atom.
LiMn(PO4)2 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form distorted LiO5 trigonal bipyramids that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 70°. The Li(1)-O(3) bond length is 1.95 Å. The Li(1)-O(5) bond length is 2.37 Å. The Li(1)-O(6) bond length is 2.05 Å. The Li(1)-O(7) bond length is 2.20 Å. The Li(1)-O(8) bond length is 2.19 Å. Mn(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a cornercorner with one Li(1)O5 trigonal bipyramid, and  an edgeedge with one Li(1)O5 trigonal bipyramid. The Mn(1)-O(1) bond length is 1.93 Å. The Mn(1)-O(2) bond length is 1.90 Å. The Mn(1)-O(4) bond length is 1.90 Å. The Mn(1)-O(5) bond length is 1.95 Å. The Mn(1)-O(7) bond length is 1.95 Å. The Mn(1)-O(8) bond length is 1.97 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and corners with two equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 45-50°. The P(1)-O(1) bond length is 1.56 Å. The P(1)-O(2) bond length is 1.56 Å. The P(1)-O(3) bond length is 1.52 Å. The P(1)-O(7) bond length is 1.58 Å. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and corners with three equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 40-47°. The P(2)-O(4) bond length is 1.54 Å. The P(2)-O(5) bond length is 1.56 Å. The P(2)-O(6) bond length is 1.55 Å. The P(2)-O(8) bond length is 1.56 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Li(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Li(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one P(2) atom.