Mn2PO5 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(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mn(2)O5 square pyramid, corners with four equivalent P(1)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with three equivalent Mn(2)O5 square pyramids. In the second Mn site, Mn(2) is bonded to one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form MnO5 square pyramids that share  a cornercorner with one Mn(1)O6 octahedra, corners with three equivalent P(1)O4 tetrahedra, edges with three equivalent Mn(1)O6 octahedra, and  an edgeedge with one Mn(2)O5 square pyramid. The corner-sharing octahedral tilt angles are 29°. P(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with four equivalent Mn(1)O6 octahedra and corners with three equivalent Mn(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 45-58°. There are five 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 to two equivalent Mn(1) and two equivalent Mn(2) atoms to form edge-sharing OMn4 trigonal pyramids. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(1) atom.
Mn2PO5 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(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mn(2)O5 square pyramid, corners with four equivalent P(1)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with three equivalent Mn(2)O5 square pyramids. The Mn(1)-O(1) bond length is 1.97 Å. The Mn(1)-O(3) bond length is 2.48 Å. The Mn(1)-O(4) bond length is 2.02 Å. The Mn(1)-O(5) bond length is 2.31 Å. There is one shorter (1.97 Å) and one longer (2.00 Å) Mn(1)-O(2) bond length. In the second Mn site, Mn(2) is bonded to one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form MnO5 square pyramids that share  a cornercorner with one Mn(1)O6 octahedra, corners with three equivalent P(1)O4 tetrahedra, edges with three equivalent Mn(1)O6 octahedra, and  an edgeedge with one Mn(2)O5 square pyramid. The corner-sharing octahedral tilt angles are 29°. The Mn(2)-O(3) bond length is 2.08 Å. The Mn(2)-O(4) bond length is 2.22 Å. The Mn(2)-O(5) bond length is 2.10 Å. There is one shorter (2.07 Å) and one longer (2.19 Å) Mn(2)-O(2) bond length. P(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with four equivalent Mn(1)O6 octahedra and corners with three equivalent Mn(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 45-58°. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.58 Å. The P(1)-O(5) bond length is 1.55 Å. There are five 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 to two equivalent Mn(1) and two equivalent Mn(2) atoms to form edge-sharing OMn4 trigonal pyramids. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(1) atom.