Ba2MgMn2(P2O7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(12), one O(2), one O(3), one O(4), one O(6), one O(9), and two equivalent O(14) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(4), one O(5), one O(9), and two equivalent O(13) atoms. Mg(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(4), and one O(7) atom. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(10), one O(12), one O(2), one O(5), and one O(6) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one O(11), one O(6), and one O(9) atom. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(10), one O(12), one O(14), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(3)O4 tetrahedra and corners with two equivalent Mn(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(11), one O(13), one O(8), and one O(9) atom to form corner-sharing PO4 tetrahedra. In the third P site, P(3) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with two equivalent Mn(1)O5 trigonal bipyramids. In the fourth P site, P(4) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and  a cornercorner with one Mn(1)O5 trigonal bipyramid. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Mg(1), and one P(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one Mn(1), and one P(3) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Mg(1), and one P(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Mn(1), and one P(4) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ba(1), one Mn(1), one Mn(2), and one P(3) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Mg(1), one P(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one P(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one Mn(2), and one P(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Ba(2), one Mn(1), and one P(1) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Ba(2), one Mn(2), and one P(2) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Ba(1), one Mn(1), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one P(2) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(1) atom.
Ba2MgMn2(P2O7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(12), one O(2), one O(3), one O(4), one O(6), one O(9), and two equivalent O(14) atoms. The Ba(1)-O(1) bond length is 3.20 Å. The Ba(1)-O(12) bond length is 2.86 Å. The Ba(1)-O(2) bond length is 2.83 Å. The Ba(1)-O(3) bond length is 3.30 Å. The Ba(1)-O(4) bond length is 2.84 Å. The Ba(1)-O(6) bond length is 2.93 Å. The Ba(1)-O(9) bond length is 2.92 Å. There is one shorter (2.89 Å) and one longer (3.07 Å) Ba(1)-O(14) bond length. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(4), one O(5), one O(9), and two equivalent O(13) atoms. The Ba(2)-O(1) bond length is 2.93 Å. The Ba(2)-O(10) bond length is 2.77 Å. The Ba(2)-O(11) bond length is 2.78 Å. The Ba(2)-O(3) bond length is 2.64 Å. The Ba(2)-O(4) bond length is 3.04 Å. The Ba(2)-O(5) bond length is 3.18 Å. The Ba(2)-O(9) bond length is 3.42 Å. There is one shorter (2.84 Å) and one longer (3.14 Å) Ba(2)-O(13) bond length. Mg(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(4), and one O(7) atom. The Mg(1)-O(1) bond length is 2.02 Å. The Mg(1)-O(4) bond length is 2.01 Å. The Mg(1)-O(7) bond length is 2.19 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(10), one O(12), one O(2), one O(5), and one O(6) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. The Mn(1)-O(10) bond length is 2.23 Å. The Mn(1)-O(12) bond length is 2.13 Å. The Mn(1)-O(2) bond length is 2.20 Å. The Mn(1)-O(5) bond length is 2.06 Å. The Mn(1)-O(6) bond length is 2.24 Å. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one O(11), one O(6), and one O(9) atom. The Mn(2)-O(11) bond length is 2.11 Å. The Mn(2)-O(6) bond length is 2.37 Å. The Mn(2)-O(9) bond length is 2.12 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(10), one O(12), one O(14), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(3)O4 tetrahedra and corners with two equivalent Mn(1)O5 trigonal bipyramids. The P(1)-O(10) bond length is 1.53 Å. The P(1)-O(12) bond length is 1.54 Å. The P(1)-O(14) bond length is 1.51 Å. The P(1)-O(7) bond length is 1.70 Å. In the second P site, P(2) is bonded to one O(11), one O(13), one O(8), and one O(9) atom to form corner-sharing PO4 tetrahedra. The P(2)-O(11) bond length is 1.54 Å. The P(2)-O(13) bond length is 1.51 Å. The P(2)-O(8) bond length is 1.67 Å. The P(2)-O(9) bond length is 1.54 Å. In the third P site, P(3) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with two equivalent Mn(1)O5 trigonal bipyramids. The P(3)-O(2) bond length is 1.54 Å. The P(3)-O(3) bond length is 1.50 Å. The P(3)-O(6) bond length is 1.56 Å. The P(3)-O(7) bond length is 1.68 Å. In the fourth P site, P(4) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and  a cornercorner with one Mn(1)O5 trigonal bipyramid. The P(4)-O(1) bond length is 1.54 Å. The P(4)-O(4) bond length is 1.55 Å. The P(4)-O(5) bond length is 1.52 Å. The P(4)-O(8) bond length is 1.62 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Mg(1), and one P(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one Mn(1), and one P(3) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Mg(1), and one P(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Mn(1), and one P(4) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ba(1), one Mn(1), one Mn(2), and one P(3) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Mg(1), one P(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one P(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one Mn(2), and one P(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Ba(2), one Mn(1), and one P(1) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Ba(2), one Mn(2), and one P(2) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Ba(1), one Mn(1), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one P(2) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(1) atom.