MgV2Mn2O7 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form VO5 trigonal bipyramids that share corners with two equivalent Mn(1)O6 pentagonal pyramids, corners with two equivalent Mn(2)O6 pentagonal pyramids,  a cornercorner with one V(2)O5 trigonal bipyramid,  an edgeedge with one Mn(1)O6 pentagonal pyramid,  an edgeedge with one Mn(2)O6 pentagonal pyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(7) atom to form VO5 trigonal bipyramids that share corners with two equivalent Mn(1)O6 pentagonal pyramids, corners with two equivalent Mn(2)O6 pentagonal pyramids,  a cornercorner with one V(1)O5 trigonal bipyramid,  an edgeedge with one Mn(1)O6 pentagonal pyramid,  an edgeedge with one Mn(2)O6 pentagonal pyramid, and  an edgeedge with one V(1)O5 trigonal bipyramid. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted MnO6 pentagonal pyramids that share corners with two equivalent V(1)O5 trigonal bipyramids, corners with two equivalent V(2)O5 trigonal bipyramids, edges with three equivalent Mn(2)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted MnO6 pentagonal pyramids that share corners with two equivalent V(1)O5 trigonal bipyramids, corners with two equivalent V(2)O5 trigonal bipyramids, edges with three equivalent Mn(1)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one V(2), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded to one Mg(1), one V(1), one Mn(1), and one Mn(2) atom to form OMgMn2V trigonal pyramids that share corners with two equivalent O(7)MgMn2V2 trigonal bipyramids,  a cornercorner with one O(6)Mn2V2 trigonal pyramid,  an edgeedge with one O(7)MgMn2V2 trigonal bipyramid, and  an edgeedge with one O(6)Mn2V2 trigonal pyramid. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one V(1), one Mn(1), and one Mn(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one V(2), one Mn(1), and one Mn(2) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Mg(1), one V(1), and one V(2) atom. In the sixth O site, O(6) is bonded to one V(1), one V(2), one Mn(1), and one Mn(2) atom to form OMn2V2 trigonal pyramids that share  a cornercorner with one O(2)MgMn2V trigonal pyramid, edges with two equivalent O(7)MgMn2V2 trigonal bipyramids, and  an edgeedge with one O(2)MgMn2V trigonal pyramid. In the seventh O site, O(7) is bonded to one Mg(1), one V(1), one V(2), one Mn(1), and one Mn(2) atom to form OMgMn2V2 trigonal bipyramids that share corners with two equivalent O(2)MgMn2V trigonal pyramids,  an edgeedge with one O(2)MgMn2V trigonal pyramid, and edges with two equivalent O(6)Mn2V2 trigonal pyramids.
MgV2Mn2O7 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. The Mg(1)-O(1) bond length is 2.07 Å. The Mg(1)-O(2) bond length is 2.06 Å. The Mg(1)-O(3) bond length is 2.13 Å. The Mg(1)-O(4) bond length is 2.68 Å. The Mg(1)-O(5) bond length is 2.01 Å. The Mg(1)-O(7) bond length is 2.12 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form VO5 trigonal bipyramids that share corners with two equivalent Mn(1)O6 pentagonal pyramids, corners with two equivalent Mn(2)O6 pentagonal pyramids,  a cornercorner with one V(2)O5 trigonal bipyramid,  an edgeedge with one Mn(1)O6 pentagonal pyramid,  an edgeedge with one Mn(2)O6 pentagonal pyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. The V(1)-O(2) bond length is 1.85 Å. The V(1)-O(3) bond length is 1.85 Å. The V(1)-O(5) bond length is 1.87 Å. The V(1)-O(6) bond length is 2.08 Å. The V(1)-O(7) bond length is 1.94 Å. In the second V site, V(2) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(7) atom to form VO5 trigonal bipyramids that share corners with two equivalent Mn(1)O6 pentagonal pyramids, corners with two equivalent Mn(2)O6 pentagonal pyramids,  a cornercorner with one V(1)O5 trigonal bipyramid,  an edgeedge with one Mn(1)O6 pentagonal pyramid,  an edgeedge with one Mn(2)O6 pentagonal pyramid, and  an edgeedge with one V(1)O5 trigonal bipyramid. The V(2)-O(1) bond length is 1.91 Å. The V(2)-O(4) bond length is 1.76 Å. The V(2)-O(5) bond length is 1.91 Å. The V(2)-O(6) bond length is 1.90 Å. The V(2)-O(7) bond length is 2.12 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted MnO6 pentagonal pyramids that share corners with two equivalent V(1)O5 trigonal bipyramids, corners with two equivalent V(2)O5 trigonal bipyramids, edges with three equivalent Mn(2)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. The Mn(1)-O(1) bond length is 2.36 Å. The Mn(1)-O(2) bond length is 2.11 Å. The Mn(1)-O(3) bond length is 2.17 Å. The Mn(1)-O(4) bond length is 2.19 Å. The Mn(1)-O(6) bond length is 2.20 Å. The Mn(1)-O(7) bond length is 2.37 Å. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted MnO6 pentagonal pyramids that share corners with two equivalent V(1)O5 trigonal bipyramids, corners with two equivalent V(2)O5 trigonal bipyramids, edges with three equivalent Mn(1)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. The Mn(2)-O(1) bond length is 2.15 Å. The Mn(2)-O(2) bond length is 2.23 Å. The Mn(2)-O(3) bond length is 2.10 Å. The Mn(2)-O(4) bond length is 2.35 Å. The Mn(2)-O(6) bond length is 2.26 Å. The Mn(2)-O(7) bond length is 2.40 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one V(2), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded to one Mg(1), one V(1), one Mn(1), and one Mn(2) atom to form OMgMn2V trigonal pyramids that share corners with two equivalent O(7)MgMn2V2 trigonal bipyramids,  a cornercorner with one O(6)Mn2V2 trigonal pyramid,  an edgeedge with one O(7)MgMn2V2 trigonal bipyramid, and  an edgeedge with one O(6)Mn2V2 trigonal pyramid. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one V(1), one Mn(1), and one Mn(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one V(2), one Mn(1), and one Mn(2) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Mg(1), one V(1), and one V(2) atom. In the sixth O site, O(6) is bonded to one V(1), one V(2), one Mn(1), and one Mn(2) atom to form OMn2V2 trigonal pyramids that share  a cornercorner with one O(2)MgMn2V trigonal pyramid, edges with two equivalent O(7)MgMn2V2 trigonal bipyramids, and  an edgeedge with one O(2)MgMn2V trigonal pyramid. In the seventh O site, O(7) is bonded to one Mg(1), one V(1), one V(2), one Mn(1), and one Mn(2) atom to form OMgMn2V2 trigonal bipyramids that share corners with two equivalent O(2)MgMn2V trigonal pyramids,  an edgeedge with one O(2)MgMn2V trigonal pyramid, and edges with two equivalent O(6)Mn2V2 trigonal pyramids.