MgMn2(P2O7)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(13), one O(2), one O(3), one O(6), and one O(9) atom. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(10), one O(12), one O(2), one O(4), and one O(5) atom to form distorted MnO6 octahedra that share  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  an edgeedge with one P(3)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to one O(11), one O(13), one O(14), one O(6), and one O(9) atom to form MnO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(8), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O5 square pyramid, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-59°. In the second P site, P(2) is bonded to one O(10), one O(11), one O(3), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O5 square pyramid, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the third P site, P(3) is bonded to one O(12), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)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 are 39°. In the fourth P site, P(4) is bonded to one O(13), one O(14), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O5 square pyramid,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 square pyramid. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Mg(1), one Mn(1), and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Mn(1) and one P(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(2), and one P(4) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(1), one Mn(2), and one P(1) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Mn(1) and one P(2) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Mn(2) and one P(2) atom. In the twelfth O site, O(12) is bonded in a water-like geometry to one Mn(1) and one P(3) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Mg(1), one Mn(2), and one P(4) atom. In the fourteenth O site, O(14) is bonded in an L-shaped geometry to one Mn(2) and one P(4) atom.
MgMn2(P2O7)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(13), one O(2), one O(3), one O(6), and one O(9) atom. The Mg(1)-O(1) bond length is 2.08 Å. The Mg(1)-O(13) bond length is 2.13 Å. The Mg(1)-O(2) bond length is 2.64 Å. The Mg(1)-O(3) bond length is 1.99 Å. The Mg(1)-O(6) bond length is 2.10 Å. The Mg(1)-O(9) bond length is 2.18 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(10), one O(12), one O(2), one O(4), and one O(5) atom to form distorted MnO6 octahedra that share  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  an edgeedge with one P(3)O4 tetrahedra. The Mn(1)-O(1) bond length is 2.56 Å. The Mn(1)-O(10) bond length is 1.95 Å. The Mn(1)-O(12) bond length is 1.95 Å. The Mn(1)-O(2) bond length is 2.02 Å. The Mn(1)-O(4) bond length is 1.94 Å. The Mn(1)-O(5) bond length is 2.49 Å. In the second Mn site, Mn(2) is bonded to one O(11), one O(13), one O(14), one O(6), and one O(9) atom to form MnO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. The Mn(2)-O(11) bond length is 2.02 Å. The Mn(2)-O(13) bond length is 2.02 Å. The Mn(2)-O(14) bond length is 1.99 Å. The Mn(2)-O(6) bond length is 1.98 Å. The Mn(2)-O(9) bond length is 1.96 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(8), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O5 square pyramid, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-59°. The P(1)-O(1) bond length is 1.52 Å. The P(1)-O(2) bond length is 1.55 Å. The P(1)-O(8) bond length is 1.58 Å. The P(1)-O(9) bond length is 1.59 Å. In the second P site, P(2) is bonded to one O(10), one O(11), one O(3), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O5 square pyramid, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. The P(2)-O(10) bond length is 1.53 Å. The P(2)-O(11) bond length is 1.52 Å. The P(2)-O(3) bond length is 1.51 Å. The P(2)-O(7) bond length is 1.70 Å. In the third P site, P(3) is bonded to one O(12), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)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 are 39°. The P(3)-O(12) bond length is 1.57 Å. The P(3)-O(4) bond length is 1.54 Å. The P(3)-O(5) bond length is 1.49 Å. The P(3)-O(8) bond length is 1.67 Å. In the fourth P site, P(4) is bonded to one O(13), one O(14), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O5 square pyramid,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 square pyramid. The P(4)-O(13) bond length is 1.55 Å. The P(4)-O(14) bond length is 1.54 Å. The P(4)-O(6) bond length is 1.58 Å. The P(4)-O(7) bond length is 1.56 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Mg(1), one Mn(1), and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Mn(1) and one P(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(2), and one P(4) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(1), one Mn(2), and one P(1) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Mn(1) and one P(2) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Mn(2) and one P(2) atom. In the twelfth O site, O(12) is bonded in a water-like geometry to one Mn(1) and one P(3) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Mg(1), one Mn(2), and one P(4) atom. In the fourteenth O site, O(14) is bonded in an L-shaped geometry to one Mn(2) and one P(4) atom.