Li2MgCo3O8 crystallizes in the monoclinic C2/m space group. Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Co(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mg(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 8-11°. Mg(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form MgO6 octahedra that share edges with two equivalent Co(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. In the second Co site, Co(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mg(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 8-11°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), one Co(1), and two equivalent Co(2) atoms to form OLi2Co3 square pyramids that share corners with five equivalent O(1)Li2Co3 square pyramids and edges with four equivalent O(3)Li2MgCo2 square pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Li(1), one Mg(1), one Co(1), and one Co(2) atom. In the third O site, O(3) is bonded to two equivalent Li(1), one Mg(1), and two equivalent Co(2) atoms to form OLi2MgCo2 square pyramids that share corners with five equivalent O(3)Li2MgCo2 square pyramids and edges with four equivalent O(1)Li2Co3 square pyramids.
Li2MgCo3O8 crystallizes in the monoclinic C2/m space group. Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Co(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mg(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 8-11°. Both Li(1)-O(1) bond lengths are 2.21 Å. Both Li(1)-O(2) bond lengths are 2.24 Å. Both Li(1)-O(3) bond lengths are 2.18 Å. Mg(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form MgO6 octahedra that share edges with two equivalent Co(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. Both Mg(1)-O(3) bond lengths are 1.98 Å. All Mg(1)-O(2) bond lengths are 2.02 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. Both Co(1)-O(1) bond lengths are 1.94 Å. All Co(1)-O(2) bond lengths are 1.87 Å. In the second Co site, Co(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mg(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 8-11°. Both Co(2)-O(1) bond lengths are 1.92 Å. Both Co(2)-O(2) bond lengths are 1.89 Å. Both Co(2)-O(3) bond lengths are 1.94 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), one Co(1), and two equivalent Co(2) atoms to form OLi2Co3 square pyramids that share corners with five equivalent O(1)Li2Co3 square pyramids and edges with four equivalent O(3)Li2MgCo2 square pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Li(1), one Mg(1), one Co(1), and one Co(2) atom. In the third O site, O(3) is bonded to two equivalent Li(1), one Mg(1), and two equivalent Co(2) atoms to form OLi2MgCo2 square pyramids that share corners with five equivalent O(3)Li2MgCo2 square pyramids and edges with four equivalent O(1)Li2Co3 square pyramids.