MgMn4O8 is beta indium sulfide-derived structured and crystallizes in the monoclinic Pc space group. Mg(1) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form MgO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra, corners with three equivalent Mn(2)O6 octahedra, corners with three equivalent Mn(3)O6 octahedra, and corners with three equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-63°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(1), one O(3), one O(4), one O(6), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mn(1), one Mn(2), and one Mn(4) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mn(1), one Mn(3), and one Mn(4) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mn(2), one Mn(3), and one Mn(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(3), and one Mn(4) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mn(2), one Mn(3), and one Mn(4) atom.
MgMn4O8 is beta indium sulfide-derived structured and crystallizes in the monoclinic Pc space group. Mg(1) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form MgO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra, corners with three equivalent Mn(2)O6 octahedra, corners with three equivalent Mn(3)O6 octahedra, and corners with three equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-63°. The Mg(1)-O(5) bond length is 2.04 Å. The Mg(1)-O(6) bond length is 1.99 Å. The Mg(1)-O(7) bond length is 2.02 Å. The Mg(1)-O(8) bond length is 2.01 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. The Mn(1)-O(1) bond length is 2.14 Å. The Mn(1)-O(2) bond length is 2.08 Å. The Mn(1)-O(3) bond length is 1.92 Å. The Mn(1)-O(5) bond length is 2.10 Å. The Mn(1)-O(6) bond length is 2.14 Å. The Mn(1)-O(7) bond length is 1.97 Å. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. The Mn(2)-O(1) bond length is 1.90 Å. The Mn(2)-O(2) bond length is 1.92 Å. The Mn(2)-O(4) bond length is 1.89 Å. The Mn(2)-O(5) bond length is 2.01 Å. The Mn(2)-O(6) bond length is 2.00 Å. The Mn(2)-O(8) bond length is 1.98 Å. In the third Mn site, Mn(3) is bonded to one O(1), one O(3), one O(4), one O(6), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. The Mn(3)-O(1) bond length is 1.90 Å. The Mn(3)-O(3) bond length is 2.10 Å. The Mn(3)-O(4) bond length is 2.13 Å. The Mn(3)-O(6) bond length is 1.95 Å. The Mn(3)-O(7) bond length is 2.17 Å. The Mn(3)-O(8) bond length is 2.08 Å. In the fourth Mn site, Mn(4) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The Mn(4)-O(2) bond length is 1.92 Å. The Mn(4)-O(3) bond length is 1.91 Å. The Mn(4)-O(4) bond length is 1.90 Å. The Mn(4)-O(5) bond length is 2.00 Å. The Mn(4)-O(7) bond length is 2.01 Å. The Mn(4)-O(8) bond length is 2.00 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mn(1), one Mn(2), and one Mn(4) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mn(1), one Mn(3), and one Mn(4) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mn(2), one Mn(3), and one Mn(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(3), and one Mn(4) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mn(2), one Mn(3), and one Mn(4) atom.