MnP2O7 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(10), one O(11), one O(3), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the second Mn site, Mn(2) is bonded to one O(11), one O(12), one O(13), one O(14), one O(4), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra,  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 corner-sharing octahedral tilt angles are 57°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(3), one O(4), one O(6), 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(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-46°. In the second P site, P(2) is bonded to one O(12), one O(2), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-44°. In the third P site, P(3) is bonded to one O(1), one O(10), one O(13), and one O(2) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-42°. In the fourth P site, P(4) is bonded to one O(11), one O(14), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one P(3) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to 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 P(1) and one P(4) atom. In the seventh O site, O(7) is bonded in an L-shaped geometry to one Mn(1) and one P(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(1) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(2) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Mn(2) and one P(3) atom. In the fourteenth O site, O(14) is bonded in a bent 120 degrees geometry to one Mn(2) and one P(4) atom.
MnP2O7 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(10), one O(11), one O(3), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. The Mn(1)-O(10) bond length is 1.91 Å. The Mn(1)-O(11) bond length is 2.03 Å. The Mn(1)-O(3) bond length is 1.90 Å. The Mn(1)-O(5) bond length is 1.92 Å. The Mn(1)-O(7) bond length is 1.98 Å. The Mn(1)-O(8) bond length is 1.95 Å. In the second Mn site, Mn(2) is bonded to one O(11), one O(12), one O(13), one O(14), one O(4), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra,  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 corner-sharing octahedral tilt angles are 57°. The Mn(2)-O(11) bond length is 2.33 Å. The Mn(2)-O(12) bond length is 1.94 Å. The Mn(2)-O(13) bond length is 2.13 Å. The Mn(2)-O(14) bond length is 2.01 Å. The Mn(2)-O(4) bond length is 1.96 Å. The Mn(2)-O(9) bond length is 1.94 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(3), one O(4), one O(6), 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(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-46°. The P(1)-O(3) bond length is 1.54 Å. The P(1)-O(4) bond length is 1.56 Å. The P(1)-O(6) bond length is 1.62 Å. The P(1)-O(9) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(12), one O(2), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-44°. The P(2)-O(12) bond length is 1.52 Å. The P(2)-O(2) bond length is 1.61 Å. The P(2)-O(5) bond length is 1.54 Å. The P(2)-O(8) bond length is 1.54 Å. In the third P site, P(3) is bonded to one O(1), one O(10), one O(13), and one O(2) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-42°. The P(3)-O(1) bond length is 1.50 Å. The P(3)-O(10) bond length is 1.53 Å. The P(3)-O(13) bond length is 1.52 Å. The P(3)-O(2) bond length is 1.68 Å. In the fourth P site, P(4) is bonded to one O(11), one O(14), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. The P(4)-O(11) bond length is 1.58 Å. The P(4)-O(14) bond length is 1.48 Å. The P(4)-O(6) bond length is 1.59 Å. The P(4)-O(7) bond length is 1.55 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one P(3) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to 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 P(1) and one P(4) atom. In the seventh O site, O(7) is bonded in an L-shaped geometry to one Mn(1) and one P(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(1) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(2) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Mn(2) and one P(3) atom. In the fourteenth O site, O(14) is bonded in a bent 120 degrees geometry to one Mn(2) and one P(4) atom.