MnPO4 crystallizes in the orthorhombic Pnma space group. Mn(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted MnO6 pentagonal pyramids that share corners with four equivalent Mn(1)O6 pentagonal pyramids, corners with four equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with four equivalent Mn(1)O6 pentagonal pyramids and  an edgeedge with one Mn(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Mn(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(1) atom.
MnPO4 crystallizes in the orthorhombic Pnma space group. Mn(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted MnO6 pentagonal pyramids that share corners with four equivalent Mn(1)O6 pentagonal pyramids, corners with four equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The Mn(1)-O(1) bond length is 1.86 Å. The Mn(1)-O(2) bond length is 1.87 Å. There are two shorter (1.99 Å) and two longer (2.30 Å) Mn(1)-O(3) bond lengths. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with four equivalent Mn(1)O6 pentagonal pyramids and  an edgeedge with one Mn(1)O6 pentagonal pyramid. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(2) bond length is 1.52 Å. Both P(1)-O(3) bond lengths are 1.55 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Mn(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(1) atom.