MgMn2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(12), one O(14), one O(15), and one O(3) atom to form MgO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Mn(6)O6 octahedra,  a cornercorner with one Mn(7)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and corners with two equivalent Mn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-64°. In the second Mg site, Mg(2) is bonded to one O(11), one O(13), one O(16), and one O(4) atom to form MgO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, and corners with two equivalent Mn(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-64°. In the third Mg site, Mg(3) is bonded to one O(11), one O(13), one O(15), one O(5), one O(7), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(12), one O(14), one O(16), one O(6), and one O(8) atom to form MgO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mn(8)O6 octahedra. There are eight inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(13), one O(15), one O(2), one O(3), one O(6), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(10), one O(11), one O(15), one O(2), one O(3), and one O(6) atom to form MnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(1)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(1), one O(11), one O(13), one O(3), one O(7), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mg(3)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(1), one O(10), one O(5), and one O(8) atom to form MnO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, corners with two equivalent Mn(7)O6 octahedra, and corners with two equivalent Mn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-69°. In the fifth Mn site, Mn(5) is bonded to one O(2), one O(6), one O(7), and one O(9) atom to form MnO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mn(6)O6 octahedra,  a cornercorner with one Mn(7)O6 octahedra,  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and corners with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-65°. In the sixth Mn site, Mn(6) is bonded to one O(1), one O(14), one O(16), one O(4), one O(5), and one O(7) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(7)O6 octahedra. In the seventh Mn site, Mn(7) is bonded to one O(1), one O(12), one O(16), one O(4), one O(5), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(6)O6 octahedra. In the eighth Mn site, Mn(8) is bonded to one O(10), one O(12), one O(14), one O(2), one O(4), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mg(4)O6 octahedra. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mn(3), one Mn(4), one Mn(6), and one Mn(7) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mn(1), one Mn(2), one Mn(5), and one Mn(8) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mn(6), one Mn(7), and one Mn(8) atom. In the fifth O site, O(5) is bonded to one Mg(3), one Mn(4), one Mn(6), and one Mn(7) atom to form distorted OMgMn3 tetrahedra that share  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(10)MgMn3 trigonal pyramid, corners with two equivalent O(16)Mg2Mn2 trigonal pyramids,  an edgeedge with one O(9)MgMn3 tetrahedra, and  an edgeedge with one O(7)MgMn3 trigonal pyramid. In the sixth O site, O(6) is bonded to one Mg(4), one Mn(1), one Mn(2), and one Mn(5) atom to form distorted OMgMn3 tetrahedra that share  a cornercorner with one O(9)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid, corners with two equivalent O(15)Mg2Mn2 trigonal pyramids, and  an edgeedge with one O(10)MgMn3 trigonal pyramid. In the seventh O site, O(7) is bonded to one Mg(3), one Mn(3), one Mn(5), and one Mn(6) atom to form distorted OMgMn3 trigonal pyramids that share  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid,  an edgeedge with one O(5)MgMn3 tetrahedra, and  an edgeedge with one O(9)MgMn3 tetrahedra. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Mn(1), one Mn(4), and one Mn(8) atom. In the ninth O site, O(9) is bonded to one Mg(3), one Mn(3), one Mn(5), and one Mn(7) atom to form distorted OMgMn3 tetrahedra that share  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid,  an edgeedge with one O(5)MgMn3 tetrahedra, and  an edgeedge with one O(7)MgMn3 trigonal pyramid. In the tenth O site, O(10) is bonded to one Mg(4), one Mn(2), one Mn(4), and one Mn(8) atom to form distorted OMgMn3 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid, corners with two equivalent O(12)Mg2Mn2 trigonal pyramids, corners with two equivalent O(14)Mg2Mn2 trigonal pyramids, and  an edgeedge with one O(6)MgMn3 tetrahedra. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mg(3), one Mn(2), and one Mn(3) atom. In the twelfth O site, O(12) is bonded to one Mg(1), one Mg(4), one Mn(7), and one Mn(8) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid, corners with two equivalent O(10)MgMn3 trigonal pyramids,  an edgeedge with one O(14)Mg2Mn2 trigonal pyramid, and  an edgeedge with one O(16)Mg2Mn2 trigonal pyramid. In the thirteenth O site, O(13) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(3), one Mn(1), and one Mn(3) atom. In the fourteenth O site, O(14) is bonded to one Mg(1), one Mg(4), one Mn(6), and one Mn(8) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid, corners with two equivalent O(10)MgMn3 trigonal pyramids,  an edgeedge with one O(12)Mg2Mn2 trigonal pyramid, and  an edgeedge with one O(16)Mg2Mn2 trigonal pyramid. In the fifteenth O site, O(15) is bonded to one Mg(1), one Mg(3), one Mn(1), and one Mn(2) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra, corners with two equivalent O(6)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(10)MgMn3 trigonal pyramid, and  a cornercorner with one O(7)MgMn3 trigonal pyramid. In the sixteenth O site, O(16) is bonded to one Mg(2), one Mg(4), one Mn(6), and one Mn(7) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra, corners with two equivalent O(5)MgMn3 tetrahedra,  a cornercorner with one O(10)MgMn3 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid,  an edgeedge with one O(12)Mg2Mn2 trigonal pyramid, and  an edgeedge with one O(14)Mg2Mn2 trigonal pyramid.
MgMn2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(12), one O(14), one O(15), and one O(3) atom to form MgO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Mn(6)O6 octahedra,  a cornercorner with one Mn(7)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and corners with two equivalent Mn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-64°. The Mg(1)-O(12) bond length is 2.03 Å. The Mg(1)-O(14) bond length is 2.05 Å. The Mg(1)-O(15) bond length is 2.02 Å. The Mg(1)-O(3) bond length is 1.99 Å. In the second Mg site, Mg(2) is bonded to one O(11), one O(13), one O(16), and one O(4) atom to form MgO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, and corners with two equivalent Mn(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-64°. The Mg(2)-O(11) bond length is 2.01 Å. The Mg(2)-O(13) bond length is 1.99 Å. The Mg(2)-O(16) bond length is 2.02 Å. The Mg(2)-O(4) bond length is 2.05 Å. In the third Mg site, Mg(3) is bonded to one O(11), one O(13), one O(15), one O(5), one O(7), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The Mg(3)-O(11) bond length is 2.08 Å. The Mg(3)-O(13) bond length is 2.07 Å. The Mg(3)-O(15) bond length is 2.10 Å. The Mg(3)-O(5) bond length is 2.11 Å. The Mg(3)-O(7) bond length is 2.12 Å. The Mg(3)-O(9) bond length is 2.07 Å. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(12), one O(14), one O(16), one O(6), and one O(8) atom to form MgO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mn(8)O6 octahedra. The Mg(4)-O(10) bond length is 2.09 Å. The Mg(4)-O(12) bond length is 2.10 Å. The Mg(4)-O(14) bond length is 2.12 Å. The Mg(4)-O(16) bond length is 2.09 Å. The Mg(4)-O(6) bond length is 2.08 Å. The Mg(4)-O(8) bond length is 2.07 Å. There are eight inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(13), one O(15), one O(2), one O(3), one O(6), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The Mn(1)-O(13) bond length is 2.25 Å. The Mn(1)-O(15) bond length is 2.00 Å. The Mn(1)-O(2) bond length is 2.02 Å. The Mn(1)-O(3) bond length is 1.94 Å. The Mn(1)-O(6) bond length is 2.00 Å. The Mn(1)-O(8) bond length is 2.21 Å. In the second Mn site, Mn(2) is bonded to one O(10), one O(11), one O(15), one O(2), one O(3), and one O(6) atom to form MnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(1)O6 octahedra. The Mn(2)-O(10) bond length is 1.99 Å. The Mn(2)-O(11) bond length is 1.97 Å. The Mn(2)-O(15) bond length is 1.97 Å. The Mn(2)-O(2) bond length is 2.28 Å. The Mn(2)-O(3) bond length is 2.23 Å. The Mn(2)-O(6) bond length is 1.96 Å. In the third Mn site, Mn(3) is bonded to one O(1), one O(11), one O(13), one O(3), one O(7), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(5)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mg(3)O6 octahedra. The Mn(3)-O(1) bond length is 2.18 Å. The Mn(3)-O(11) bond length is 2.04 Å. The Mn(3)-O(13) bond length is 1.93 Å. The Mn(3)-O(3) bond length is 2.22 Å. The Mn(3)-O(7) bond length is 2.01 Å. The Mn(3)-O(9) bond length is 2.04 Å. In the fourth Mn site, Mn(4) is bonded to one O(1), one O(10), one O(5), and one O(8) atom to form MnO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Mn(6)O6 octahedra, corners with two equivalent Mn(7)O6 octahedra, and corners with two equivalent Mn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-69°. The Mn(4)-O(1) bond length is 2.02 Å. The Mn(4)-O(10) bond length is 2.05 Å. The Mn(4)-O(5) bond length is 2.05 Å. The Mn(4)-O(8) bond length is 2.01 Å. In the fifth Mn site, Mn(5) is bonded to one O(2), one O(6), one O(7), and one O(9) atom to form MnO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mn(6)O6 octahedra,  a cornercorner with one Mn(7)O6 octahedra,  a cornercorner with one Mn(8)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and corners with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-65°. The Mn(5)-O(2) bond length is 2.08 Å. The Mn(5)-O(6) bond length is 2.06 Å. The Mn(5)-O(7) bond length is 2.09 Å. The Mn(5)-O(9) bond length is 2.05 Å. In the sixth Mn site, Mn(6) is bonded to one O(1), one O(14), one O(16), one O(4), one O(5), and one O(7) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(7)O6 octahedra. The Mn(6)-O(1) bond length is 1.90 Å. The Mn(6)-O(14) bond length is 1.99 Å. The Mn(6)-O(16) bond length is 1.96 Å. The Mn(6)-O(4) bond length is 1.97 Å. The Mn(6)-O(5) bond length is 1.94 Å. The Mn(6)-O(7) bond length is 1.98 Å. In the seventh Mn site, Mn(7) is bonded to one O(1), one O(12), one O(16), one O(4), one O(5), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(8)O6 octahedra, and edges with two equivalent Mn(6)O6 octahedra. The Mn(7)-O(1) bond length is 2.20 Å. The Mn(7)-O(12) bond length is 1.98 Å. The Mn(7)-O(16) bond length is 1.98 Å. The Mn(7)-O(4) bond length is 2.29 Å. The Mn(7)-O(5) bond length is 1.98 Å. The Mn(7)-O(9) bond length is 1.95 Å. In the eighth Mn site, Mn(8) is bonded to one O(10), one O(12), one O(14), one O(2), one O(4), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Mn(5)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(6)O6 octahedra,  an edgeedge with one Mn(7)O6 octahedra, and edges with two equivalent Mg(4)O6 octahedra. The Mn(8)-O(10) bond length is 1.95 Å. The Mn(8)-O(12) bond length is 1.97 Å. The Mn(8)-O(14) bond length is 1.99 Å. The Mn(8)-O(2) bond length is 1.97 Å. The Mn(8)-O(4) bond length is 1.99 Å. The Mn(8)-O(8) bond length is 1.90 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mn(3), one Mn(4), one Mn(6), and one Mn(7) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mn(1), one Mn(2), one Mn(5), and one Mn(8) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mn(6), one Mn(7), and one Mn(8) atom. In the fifth O site, O(5) is bonded to one Mg(3), one Mn(4), one Mn(6), and one Mn(7) atom to form distorted OMgMn3 tetrahedra that share  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(10)MgMn3 trigonal pyramid, corners with two equivalent O(16)Mg2Mn2 trigonal pyramids,  an edgeedge with one O(9)MgMn3 tetrahedra, and  an edgeedge with one O(7)MgMn3 trigonal pyramid. In the sixth O site, O(6) is bonded to one Mg(4), one Mn(1), one Mn(2), and one Mn(5) atom to form distorted OMgMn3 tetrahedra that share  a cornercorner with one O(9)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid, corners with two equivalent O(15)Mg2Mn2 trigonal pyramids, and  an edgeedge with one O(10)MgMn3 trigonal pyramid. In the seventh O site, O(7) is bonded to one Mg(3), one Mn(3), one Mn(5), and one Mn(6) atom to form distorted OMgMn3 trigonal pyramids that share  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid,  an edgeedge with one O(5)MgMn3 tetrahedra, and  an edgeedge with one O(9)MgMn3 tetrahedra. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Mn(1), one Mn(4), and one Mn(8) atom. In the ninth O site, O(9) is bonded to one Mg(3), one Mn(3), one Mn(5), and one Mn(7) atom to form distorted OMgMn3 tetrahedra that share  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid,  an edgeedge with one O(5)MgMn3 tetrahedra, and  an edgeedge with one O(7)MgMn3 trigonal pyramid. In the tenth O site, O(10) is bonded to one Mg(4), one Mn(2), one Mn(4), and one Mn(8) atom to form distorted OMgMn3 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(16)Mg2Mn2 trigonal pyramid, corners with two equivalent O(12)Mg2Mn2 trigonal pyramids, corners with two equivalent O(14)Mg2Mn2 trigonal pyramids, and  an edgeedge with one O(6)MgMn3 tetrahedra. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mg(3), one Mn(2), and one Mn(3) atom. In the twelfth O site, O(12) is bonded to one Mg(1), one Mg(4), one Mn(7), and one Mn(8) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid, corners with two equivalent O(10)MgMn3 trigonal pyramids,  an edgeedge with one O(14)Mg2Mn2 trigonal pyramid, and  an edgeedge with one O(16)Mg2Mn2 trigonal pyramid. In the thirteenth O site, O(13) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(3), one Mn(1), and one Mn(3) atom. In the fourteenth O site, O(14) is bonded to one Mg(1), one Mg(4), one Mn(6), and one Mn(8) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(15)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid, corners with two equivalent O(10)MgMn3 trigonal pyramids,  an edgeedge with one O(12)Mg2Mn2 trigonal pyramid, and  an edgeedge with one O(16)Mg2Mn2 trigonal pyramid. In the fifteenth O site, O(15) is bonded to one Mg(1), one Mg(3), one Mn(1), and one Mn(2) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(5)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra, corners with two equivalent O(6)MgMn3 tetrahedra,  a cornercorner with one O(12)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(14)Mg2Mn2 trigonal pyramid,  a cornercorner with one O(10)MgMn3 trigonal pyramid, and  a cornercorner with one O(7)MgMn3 trigonal pyramid. In the sixteenth O site, O(16) is bonded to one Mg(2), one Mg(4), one Mn(6), and one Mn(7) atom to form distorted OMg2Mn2 trigonal pyramids that share  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(9)MgMn3 tetrahedra, corners with two equivalent O(5)MgMn3 tetrahedra,  a cornercorner with one O(10)MgMn3 trigonal pyramid,  a cornercorner with one O(7)MgMn3 trigonal pyramid,  an edgeedge with one O(12)Mg2Mn2 trigonal pyramid, and  an edgeedge with one O(14)Mg2Mn2 trigonal pyramid.