MgMn4Zn2O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(6) atoms to form distorted MgO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mg(1)O4 tetrahedra, corners with four equivalent Zn(1)O5 trigonal bipyramids, edges with two equivalent Mn(4)O6 octahedra, and  an edgeedge with one Zn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 30°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(5), two equivalent O(4), and two equivalent O(7) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(2)O5 square pyramids,  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(3)O5 trigonal bipyramid, edges with two equivalent 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(4), two equivalent O(3), and two equivalent O(7) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 7-8°. In the third Mn site, Mn(3) is bonded to one O(5), two equivalent O(1), and two equivalent O(8) atoms to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Mn(1)O6 octahedra, corners with four equivalent Mn(4)O6 octahedra, corners with two equivalent Zn(1)O5 trigonal bipyramids,  an edgeedge with one Mn(4)O6 octahedra, and edges with two equivalent Mn(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 15-73°. In the fourth Mn site, Mn(4) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Zn(1)O5 trigonal bipyramids, corners with four equivalent Mn(3)O5 trigonal bipyramids, edges with two equivalent Mn(4)O6 octahedra, edges with two equivalent Mg(1)O4 tetrahedra,  an edgeedge with one Mn(3)O5 trigonal bipyramid, and edges with three equivalent Zn(1)O5 trigonal bipyramids. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(8), two equivalent O(2), and two equivalent O(6) atoms to form ZnO5 trigonal bipyramids that share corners with two equivalent Mn(4)O6 octahedra, corners with four equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(3)O5 trigonal bipyramids, edges with three equivalent Mn(4)O6 octahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and edges with two equivalent Zn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 29°. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(4), and two equivalent O(5) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Mn(4) and two equivalent Mn(3) atoms. In the second O site, O(2) is bonded to one Mg(1), two equivalent Mn(4), and two equivalent Zn(1) atoms to form distorted OMgMn2Zn2 trigonal bipyramids that share corners with two equivalent O(6)Mg2MnZn2 square pyramids, corners with four equivalent O(8)Mn4Zn square pyramids,  an edgeedge with one O(8)Mn4Zn square pyramid, edges with three equivalent O(6)Mg2MnZn2 square pyramids, and edges with two equivalent O(2)MgMn2Zn2 trigonal bipyramids. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Mn(2), two equivalent Mn(1), and two equivalent Zn(2) atoms to form OMn3Zn2 square pyramids that share corners with two equivalent O(7)Mn4Zn square pyramids, corners with four equivalent O(5)Mn2Zn2 tetrahedra, edges with two equivalent O(4)Mn3Zn2 square pyramids, edges with three equivalent O(7)Mn4Zn square pyramids, and  an edgeedge with one O(5)Mn2Zn2 tetrahedra. In the fifth O site, O(5) is bonded to one Mn(1), one Mn(3), and two equivalent Zn(2) atoms to form OMn2Zn2 tetrahedra that share corners with two equivalent O(8)Mn4Zn square pyramids, corners with four equivalent O(4)Mn3Zn2 square pyramids, corners with two equivalent O(5)Mn2Zn2 tetrahedra,  an edgeedge with one O(4)Mn3Zn2 square pyramid, and edges with two equivalent O(7)Mn4Zn square pyramids. In the sixth O site, O(6) is bonded to two equivalent Mg(1), one Mn(4), and two equivalent Zn(1) atoms to form OMg2MnZn2 square pyramids that share corners with two equivalent O(2)MgMn2Zn2 trigonal bipyramids, edges with two equivalent O(6)Mg2MnZn2 square pyramids, edges with two equivalent O(8)Mn4Zn square pyramids, and edges with three equivalent O(2)MgMn2Zn2 trigonal bipyramids. In the seventh O site, O(7) is bonded to two equivalent Mn(1), two equivalent Mn(2), and one Zn(2) atom to form distorted OMn4Zn square pyramids that share corners with two equivalent O(4)Mn3Zn2 square pyramids, edges with two equivalent O(7)Mn4Zn square pyramids, edges with three equivalent O(4)Mn3Zn2 square pyramids, and edges with two equivalent O(5)Mn2Zn2 tetrahedra. In the eighth O site, O(8) is bonded to two equivalent Mn(3), two equivalent Mn(4), and one Zn(1) atom to form OMn4Zn square pyramids that share corners with two equivalent O(5)Mn2Zn2 tetrahedra, corners with four equivalent O(2)MgMn2Zn2 trigonal bipyramids, edges with two equivalent O(6)Mg2MnZn2 square pyramids, edges with two equivalent O(8)Mn4Zn square pyramids, and  an edgeedge with one O(2)MgMn2Zn2 trigonal bipyramid.
MgMn4Zn2O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(6) atoms to form distorted MgO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mg(1)O4 tetrahedra, corners with four equivalent Zn(1)O5 trigonal bipyramids, edges with two equivalent Mn(4)O6 octahedra, and  an edgeedge with one Zn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 30°. The Mg(1)-O(2) bond length is 2.00 Å. The Mg(1)-O(3) bond length is 1.94 Å. Both Mg(1)-O(6) bond lengths are 1.98 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(5), two equivalent O(4), and two equivalent O(7) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(2)O5 square pyramids,  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(3)O5 trigonal bipyramid, edges with two equivalent Mn(1)O6 octahedra, and edges with three equivalent Mn(2)O5 square pyramids. The Mn(1)-O(3) bond length is 2.76 Å. The Mn(1)-O(5) bond length is 2.15 Å. There is one shorter (2.10 Å) and one longer (2.14 Å) Mn(1)-O(4) bond length. There is one shorter (2.18 Å) and one longer (2.26 Å) Mn(1)-O(7) bond length. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(3), and two equivalent O(7) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 7-8°. The Mn(2)-O(4) bond length is 2.16 Å. Both Mn(2)-O(3) bond lengths are 1.97 Å. There is one shorter (2.02 Å) and one longer (2.03 Å) Mn(2)-O(7) bond length. In the third Mn site, Mn(3) is bonded to one O(5), two equivalent O(1), and two equivalent O(8) atoms to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Mn(1)O6 octahedra, corners with four equivalent Mn(4)O6 octahedra, corners with two equivalent Zn(1)O5 trigonal bipyramids,  an edgeedge with one Mn(4)O6 octahedra, and edges with two equivalent Mn(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 15-73°. The Mn(3)-O(5) bond length is 2.04 Å. There is one shorter (1.95 Å) and one longer (2.00 Å) Mn(3)-O(1) bond length. There is one shorter (2.06 Å) and one longer (2.16 Å) Mn(3)-O(8) bond length. In the fourth Mn site, Mn(4) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Zn(1)O5 trigonal bipyramids, corners with four equivalent Mn(3)O5 trigonal bipyramids, edges with two equivalent Mn(4)O6 octahedra, edges with two equivalent Mg(1)O4 tetrahedra,  an edgeedge with one Mn(3)O5 trigonal bipyramid, and edges with three equivalent Zn(1)O5 trigonal bipyramids. The Mn(4)-O(1) bond length is 2.08 Å. The Mn(4)-O(6) bond length is 2.31 Å. There is one shorter (2.26 Å) and one longer (2.32 Å) Mn(4)-O(2) bond length. There is one shorter (2.19 Å) and one longer (2.22 Å) Mn(4)-O(8) bond length. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(8), two equivalent O(2), and two equivalent O(6) atoms to form ZnO5 trigonal bipyramids that share corners with two equivalent Mn(4)O6 octahedra, corners with four equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(3)O5 trigonal bipyramids, edges with three equivalent Mn(4)O6 octahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and edges with two equivalent Zn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 29°. The Zn(1)-O(8) bond length is 2.11 Å. There is one shorter (2.06 Å) and one longer (2.08 Å) Zn(1)-O(2) bond length. There is one shorter (2.10 Å) and one longer (2.15 Å) Zn(1)-O(6) bond length. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(4), and two equivalent O(5) atoms. The Zn(2)-O(7) bond length is 2.51 Å. There is one shorter (2.14 Å) and one longer (2.17 Å) Zn(2)-O(4) bond length. There is one shorter (1.99 Å) and one longer (2.04 Å) Zn(2)-O(5) bond length. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Mn(4) and two equivalent Mn(3) atoms. In the second O site, O(2) is bonded to one Mg(1), two equivalent Mn(4), and two equivalent Zn(1) atoms to form distorted OMgMn2Zn2 trigonal bipyramids that share corners with two equivalent O(6)Mg2MnZn2 square pyramids, corners with four equivalent O(8)Mn4Zn square pyramids,  an edgeedge with one O(8)Mn4Zn square pyramid, edges with three equivalent O(6)Mg2MnZn2 square pyramids, and edges with two equivalent O(2)MgMn2Zn2 trigonal bipyramids. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Mn(2), two equivalent Mn(1), and two equivalent Zn(2) atoms to form OMn3Zn2 square pyramids that share corners with two equivalent O(7)Mn4Zn square pyramids, corners with four equivalent O(5)Mn2Zn2 tetrahedra, edges with two equivalent O(4)Mn3Zn2 square pyramids, edges with three equivalent O(7)Mn4Zn square pyramids, and  an edgeedge with one O(5)Mn2Zn2 tetrahedra. In the fifth O site, O(5) is bonded to one Mn(1), one Mn(3), and two equivalent Zn(2) atoms to form OMn2Zn2 tetrahedra that share corners with two equivalent O(8)Mn4Zn square pyramids, corners with four equivalent O(4)Mn3Zn2 square pyramids, corners with two equivalent O(5)Mn2Zn2 tetrahedra,  an edgeedge with one O(4)Mn3Zn2 square pyramid, and edges with two equivalent O(7)Mn4Zn square pyramids. In the sixth O site, O(6) is bonded to two equivalent Mg(1), one Mn(4), and two equivalent Zn(1) atoms to form OMg2MnZn2 square pyramids that share corners with two equivalent O(2)MgMn2Zn2 trigonal bipyramids, edges with two equivalent O(6)Mg2MnZn2 square pyramids, edges with two equivalent O(8)Mn4Zn square pyramids, and edges with three equivalent O(2)MgMn2Zn2 trigonal bipyramids. In the seventh O site, O(7) is bonded to two equivalent Mn(1), two equivalent Mn(2), and one Zn(2) atom to form distorted OMn4Zn square pyramids that share corners with two equivalent O(4)Mn3Zn2 square pyramids, edges with two equivalent O(7)Mn4Zn square pyramids, edges with three equivalent O(4)Mn3Zn2 square pyramids, and edges with two equivalent O(5)Mn2Zn2 tetrahedra. In the eighth O site, O(8) is bonded to two equivalent Mn(3), two equivalent Mn(4), and one Zn(1) atom to form OMn4Zn square pyramids that share corners with two equivalent O(5)Mn2Zn2 tetrahedra, corners with four equivalent O(2)MgMn2Zn2 trigonal bipyramids, edges with two equivalent O(6)Mg2MnZn2 square pyramids, edges with two equivalent O(8)Mn4Zn square pyramids, and  an edgeedge with one O(2)MgMn2Zn2 trigonal bipyramid.