MgMn(CoO3)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(3), one O(6), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-23°. Mn(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-12°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(6) atoms to form CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 18°. In the second Co site, Co(2) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 23°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Mn(1) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded to two equivalent Mg(1), two equivalent Mn(1), and one Co(2) atom to form OMg2Mn2Co square pyramids that share corners with four equivalent O(4)Mg2Mn2Co square pyramids, corners with three equivalent O(6)MgCo3 trigonal pyramids, edges with two equivalent O(2)Mg2Mn2Co square pyramids, and edges with two equivalent O(4)Mg2Mn2Co square pyramids. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded to two equivalent Mg(1), two equivalent Mn(1), and one Co(1) atom to form OMg2Mn2Co square pyramids that share corners with four equivalent O(2)Mg2Mn2Co square pyramids, edges with two equivalent O(2)Mg2Mn2Co square pyramids, edges with two equivalent O(4)Mg2Mn2Co square pyramids, and edges with two equivalent O(6)MgCo3 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Co(2) atoms. In the sixth O site, O(6) is bonded to one Mg(1), one Co(2), and two equivalent Co(1) atoms to form OMgCo3 trigonal pyramids that share corners with three equivalent O(2)Mg2Mn2Co square pyramids, corners with two equivalent O(6)MgCo3 trigonal pyramids, and edges with two equivalent O(4)Mg2Mn2Co square pyramids.
MgMn(CoO3)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(3), one O(6), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-23°. The Mg(1)-O(3) bond length is 2.10 Å. The Mg(1)-O(6) bond length is 2.11 Å. Both Mg(1)-O(2) bond lengths are 2.10 Å. There is one shorter (2.13 Å) and one longer (2.14 Å) Mg(1)-O(4) bond length. Mn(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-12°. The Mn(1)-O(1) bond length is 1.97 Å. The Mn(1)-O(5) bond length is 1.93 Å. There is one shorter (1.96 Å) and one longer (2.29 Å) Mn(1)-O(2) bond length. There is one shorter (2.00 Å) and one longer (2.32 Å) Mn(1)-O(4) bond length. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(6) atoms to form CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 18°. The Co(1)-O(3) bond length is 1.87 Å. The Co(1)-O(4) bond length is 1.92 Å. There is one shorter (1.89 Å) and one longer (1.94 Å) Co(1)-O(1) bond length. There is one shorter (1.93 Å) and one longer (1.95 Å) Co(1)-O(6) bond length. In the second Co site, Co(2) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 23°. The Co(2)-O(2) bond length is 2.13 Å. The Co(2)-O(6) bond length is 1.99 Å. There is one shorter (2.03 Å) and one longer (2.10 Å) Co(2)-O(3) bond length. There is one shorter (1.84 Å) and one longer (2.06 Å) Co(2)-O(5) bond length. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Mn(1) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded to two equivalent Mg(1), two equivalent Mn(1), and one Co(2) atom to form OMg2Mn2Co square pyramids that share corners with four equivalent O(4)Mg2Mn2Co square pyramids, corners with three equivalent O(6)MgCo3 trigonal pyramids, edges with two equivalent O(2)Mg2Mn2Co square pyramids, and edges with two equivalent O(4)Mg2Mn2Co square pyramids. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded to two equivalent Mg(1), two equivalent Mn(1), and one Co(1) atom to form OMg2Mn2Co square pyramids that share corners with four equivalent O(2)Mg2Mn2Co square pyramids, edges with two equivalent O(2)Mg2Mn2Co square pyramids, edges with two equivalent O(4)Mg2Mn2Co square pyramids, and edges with two equivalent O(6)MgCo3 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Co(2) atoms. In the sixth O site, O(6) is bonded to one Mg(1), one Co(2), and two equivalent Co(1) atoms to form OMgCo3 trigonal pyramids that share corners with three equivalent O(2)Mg2Mn2Co square pyramids, corners with two equivalent O(6)MgCo3 trigonal pyramids, and edges with two equivalent O(4)Mg2Mn2Co square pyramids.