MnPO4 crystallizes in the triclinic P-1 space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to one O(1), one O(5), one O(6), one O(7), and two equivalent O(2) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O5 trigonal bipyramid. In the second P site, P(2) is bonded to one O(3), one O(4), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O5 trigonal bipyramids and  an edgeedge with one Mn(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Mn(2) and one P(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Mn(2) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(2) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to one Mn(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Mn(1), one Mn(2), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1), one Mn(2), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(2) atom.
MnPO4 crystallizes in the triclinic P-1 space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The Mn(1)-O(3) bond length is 1.93 Å. The Mn(1)-O(4) bond length is 2.10 Å. The Mn(1)-O(5) bond length is 1.97 Å. The Mn(1)-O(6) bond length is 2.08 Å. The Mn(1)-O(8) bond length is 1.89 Å. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to one O(1), one O(5), one O(6), one O(7), and two equivalent O(2) atoms. The Mn(2)-O(1) bond length is 2.04 Å. The Mn(2)-O(5) bond length is 2.63 Å. The Mn(2)-O(6) bond length is 2.17 Å. The Mn(2)-O(7) bond length is 1.94 Å. There is one shorter (2.07 Å) and one longer (2.11 Å) Mn(2)-O(2) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O5 trigonal bipyramid. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(2) bond length is 1.59 Å. The P(1)-O(5) bond length is 1.54 Å. The P(1)-O(7) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(3), one O(4), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O5 trigonal bipyramids and  an edgeedge with one Mn(1)O5 trigonal bipyramid. The P(2)-O(3) bond length is 1.54 Å. The P(2)-O(4) bond length is 1.53 Å. The P(2)-O(6) bond length is 1.60 Å. The P(2)-O(8) bond length is 1.54 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Mn(2) and one P(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Mn(2) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one P(2) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to one Mn(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Mn(1), one Mn(2), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1), one Mn(2), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(2) atom.