MgMn2Al2O6 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Al(1)O6 octahedra and faces with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 36°. Mn(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted AlO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, edges with three equivalent Al(1)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 36°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mn(1), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mn(1), and two equivalent Al(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mn(1), and two equivalent Al(1) atoms.
MgMn2Al2O6 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Al(1)O6 octahedra and faces with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 36°. Both Mg(1)-O(1) bond lengths are 2.07 Å. Both Mg(1)-O(2) bond lengths are 2.06 Å. Both Mg(1)-O(3) bond lengths are 2.07 Å. Mn(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There is one shorter (2.09 Å) and one longer (2.54 Å) Mn(1)-O(1) bond length. There is one shorter (2.09 Å) and one longer (2.57 Å) Mn(1)-O(2) bond length. There is one shorter (2.09 Å) and one longer (2.53 Å) Mn(1)-O(3) bond length. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted AlO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, edges with three equivalent Al(1)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 36°. There is one shorter (1.89 Å) and one longer (2.03 Å) Al(1)-O(1) bond length. There is one shorter (1.89 Å) and one longer (2.02 Å) Al(1)-O(2) bond length. There is one shorter (1.89 Å) and one longer (2.03 Å) Al(1)-O(3) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mn(1), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mn(1), and two equivalent Al(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mn(1), and two equivalent Al(1) atoms.