Li5Mn2CoO8 is Caswellsilverite-derived structured and crystallizes in the monoclinic P2/m space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form LiO6 octahedra that share corners with three equivalent Li(3)O6 octahedra, corners with three equivalent Co(1)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-14°. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms. In the third Li site, Li(3) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MnO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Li(3)O6 octahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form MnO6 octahedra that share edges with two equivalent Mn(2)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. Co(1) is bonded to two equivalent O(2) and four equivalent O(4) 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 Co(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-14°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(3), two equivalent Li(2), and two equivalent Mn(1) atoms to form OLi4Mn2 octahedra that share corners with three equivalent O(2)Li3Mn2Co octahedra, corners with three equivalent O(1)Li4Mn2 octahedra,  an edgeedge with one O(2)Li3Mn2Co octahedra, edges with three equivalent O(1)Li4Mn2 octahedra, and edges with six equivalent O(3)Li5Mn octahedra. The corner-sharing octahedral tilt angles range from 0-16°. In the second O site, O(2) is bonded to one Li(1), two equivalent Li(2), two equivalent Mn(2), and one Co(1) atom to form OLi3Mn2Co octahedra that share corners with three equivalent O(2)Li3Mn2Co octahedra, corners with three equivalent O(1)Li4Mn2 octahedra,  an edgeedge with one O(1)Li4Mn2 octahedra, edges with two equivalent O(3)Li5Mn octahedra, and edges with three equivalent O(2)Li3Mn2Co octahedra. The corner-sharing octahedral tilt angles range from 0-16°. In the third O site, O(3) is bonded to one Li(2), two equivalent Li(1), two equivalent Li(3), and one Mn(1) atom to form OLi5Mn octahedra that share corners with three equivalent O(3)Li5Mn octahedra, edges with two equivalent O(2)Li3Mn2Co octahedra, edges with three equivalent O(3)Li5Mn octahedra, and edges with six equivalent O(1)Li4Mn2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Li(2), two equivalent Li(1), one Mn(2), and two equivalent Co(1) atoms.
Li5Mn2CoO8 is Caswellsilverite-derived structured and crystallizes in the monoclinic P2/m space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form LiO6 octahedra that share corners with three equivalent Li(3)O6 octahedra, corners with three equivalent Co(1)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-14°. The Li(1)-O(1) bond length is 2.03 Å. The Li(1)-O(2) bond length is 2.15 Å. Both Li(1)-O(3) bond lengths are 1.98 Å. Both Li(1)-O(4) bond lengths are 2.28 Å. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms. The Li(2)-O(3) bond length is 1.99 Å. The Li(2)-O(4) bond length is 2.61 Å. Both Li(2)-O(1) bond lengths are 2.07 Å. Both Li(2)-O(2) bond lengths are 2.34 Å. In the third Li site, Li(3) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. Both Li(3)-O(1) bond lengths are 2.10 Å. All Li(3)-O(3) bond lengths are 2.09 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MnO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Li(3)O6 octahedra. Both Mn(1)-O(3) bond lengths are 1.92 Å. All Mn(1)-O(1) bond lengths are 1.97 Å. In the second Mn site, Mn(2) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form MnO6 octahedra that share edges with two equivalent Mn(2)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. Both Mn(2)-O(4) bond lengths are 1.94 Å. All Mn(2)-O(2) bond lengths are 1.94 Å. Co(1) is bonded to two equivalent O(2) and four equivalent O(4) 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 Co(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-14°. Both Co(1)-O(2) bond lengths are 2.18 Å. All Co(1)-O(4) bond lengths are 1.97 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(3), two equivalent Li(2), and two equivalent Mn(1) atoms to form OLi4Mn2 octahedra that share corners with three equivalent O(2)Li3Mn2Co octahedra, corners with three equivalent O(1)Li4Mn2 octahedra,  an edgeedge with one O(2)Li3Mn2Co octahedra, edges with three equivalent O(1)Li4Mn2 octahedra, and edges with six equivalent O(3)Li5Mn octahedra. The corner-sharing octahedral tilt angles range from 0-16°. In the second O site, O(2) is bonded to one Li(1), two equivalent Li(2), two equivalent Mn(2), and one Co(1) atom to form OLi3Mn2Co octahedra that share corners with three equivalent O(2)Li3Mn2Co octahedra, corners with three equivalent O(1)Li4Mn2 octahedra,  an edgeedge with one O(1)Li4Mn2 octahedra, edges with two equivalent O(3)Li5Mn octahedra, and edges with three equivalent O(2)Li3Mn2Co octahedra. The corner-sharing octahedral tilt angles range from 0-16°. In the third O site, O(3) is bonded to one Li(2), two equivalent Li(1), two equivalent Li(3), and one Mn(1) atom to form OLi5Mn octahedra that share corners with three equivalent O(3)Li5Mn octahedra, edges with two equivalent O(2)Li3Mn2Co octahedra, edges with three equivalent O(3)Li5Mn octahedra, and edges with six equivalent O(1)Li4Mn2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Li(2), two equivalent Li(1), one Mn(2), and two equivalent Co(1) atoms.