MgMn4O8 crystallizes in the orthorhombic F222 space group. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(2) atoms. Mn(1) is bonded to two equivalent O(2) and three equivalent O(1) atoms to form distorted edge-sharing MnO5 trigonal bipyramids. There are two inequivalent O sites. In the first O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1) and two equivalent Mn(1) atoms. In the second O site, O(1) is bonded in a distorted T-shaped geometry to three equivalent Mn(1) atoms.
MgMn4O8 crystallizes in the orthorhombic F222 space group. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(2) atoms. All Mg(1)-O(2) bond lengths are 2.03 Å. Mn(1) is bonded to two equivalent O(2) and three equivalent O(1) atoms to form distorted edge-sharing MnO5 trigonal bipyramids. Both Mn(1)-O(2) bond lengths are 1.94 Å. There are two shorter (1.96 Å) and one longer (1.99 Å) Mn(1)-O(1) bond length. There are two inequivalent O sites. In the first O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1) and two equivalent Mn(1) atoms. In the second O site, O(1) is bonded in a distorted T-shaped geometry to three equivalent Mn(1) atoms.