Li9Mn5O12 crystallizes in the monoclinic C2/c space group. There are six inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted LiO6 octahedra that share corners with two equivalent Li(3)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(1)O5 square pyramids. In the second Li site, Li(2) is bonded in a 3-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(1) atoms. In the third Li site, Li(3) is bonded to one O(2), one O(4), one O(6), and two equivalent O(3) atoms to form distorted LiO5 square pyramids that share  a cornercorner with one Li(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, corners with three equivalent Mn(1)O5 square pyramids,  an edgeedge with one Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra,  an edgeedge with one Li(3)O5 square pyramid,  an edgeedge with one Mn(1)O5 square pyramid, and  an edgeedge with one Li(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-85°. In the fourth Li site, Li(4) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(1)O5 square pyramids, and edges with two equivalent Li(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 49-67°. In the fifth Li site, Li(5) is bonded in a 3-coordinate geometry to one O(4), one O(5), and two equivalent O(2) atoms. In the sixth Li site, Li(6) is bonded in a 4-coordinate geometry to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with three equivalent Li(3)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Li(3)O5 square pyramid, and  an edgeedge with one Mn(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 84-87°. In the second Mn site, Mn(2) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Li(3)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Li(3)O5 square pyramids, and edges with two equivalent Mn(1)O5 square pyramids. In the third Mn site, Mn(3) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(6) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Li(3)O5 square pyramid, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(1)O5 square pyramid, and edges with two equivalent Li(3)O5 square pyramids. There are six inequivalent O sites. In the first O site, O(6) is bonded to one Li(2), one Li(3), one Li(6), and two equivalent Mn(3) atoms to form OLi3Mn2 square pyramids that share  a cornercorner with one O(5)Li4Mn2 octahedra, corners with two equivalent O(1)Li4Mn2 octahedra,  a cornercorner with one O(6)Li3Mn2 square pyramid,  an edgeedge with one O(1)Li4Mn2 octahedra, edges with two equivalent O(5)Li4Mn2 octahedra, and  an edgeedge with one O(6)Li3Mn2 square pyramid. The corner-sharing octahedral tilt angles range from 8-11°. In the second O site, O(1) is bonded to one Li(1), one Li(4), two equivalent Li(2), one Mn(1), and one Mn(3) atom to form distorted OLi4Mn2 octahedra that share  a cornercorner with one O(1)Li4Mn2 octahedra,  a cornercorner with one O(5)Li4Mn2 octahedra, corners with two equivalent O(6)Li3Mn2 square pyramids, edges with two equivalent O(5)Li4Mn2 octahedra,  an edgeedge with one O(6)Li3Mn2 square pyramid, and  a faceface with one O(1)Li4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-11°. In the third O site, O(2) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(5), one Mn(3), and two equivalent Mn(1) atoms. In the fourth O site, O(3) is bonded in a 7-coordinate geometry to one Li(2), one Li(4), two equivalent Li(3), one Mn(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to one Li(1), one Li(3), one Li(5), one Li(6), one Mn(1), and one Mn(2) atom. In the sixth O site, O(5) is bonded to one Li(1), one Li(2), one Li(5), one Li(6), one Mn(2), and one Mn(3) atom to form distorted OLi4Mn2 octahedra that share  a cornercorner with one O(1)Li4Mn2 octahedra, corners with three equivalent O(5)Li4Mn2 octahedra,  a cornercorner with one O(6)Li3Mn2 square pyramid, edges with two equivalent O(1)Li4Mn2 octahedra, and edges with two equivalent O(6)Li3Mn2 square pyramids. The corner-sharing octahedral tilt angles range from 0-11°.
Li9Mn5O12 crystallizes in the monoclinic C2/c space group. There are six inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted LiO6 octahedra that share corners with two equivalent Li(3)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(1)O5 square pyramids. Both Li(1)-O(1) bond lengths are 2.08 Å. Both Li(1)-O(4) bond lengths are 2.58 Å. Both Li(1)-O(5) bond lengths are 2.09 Å. In the second Li site, Li(2) is bonded in a 3-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(1) atoms. The Li(2)-O(2) bond length is 2.44 Å. The Li(2)-O(3) bond length is 2.53 Å. The Li(2)-O(5) bond length is 1.93 Å. The Li(2)-O(6) bond length is 1.93 Å. There is one shorter (2.02 Å) and one longer (2.45 Å) Li(2)-O(1) bond length. In the third Li site, Li(3) is bonded to one O(2), one O(4), one O(6), and two equivalent O(3) atoms to form distorted LiO5 square pyramids that share  a cornercorner with one Li(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, corners with three equivalent Mn(1)O5 square pyramids,  an edgeedge with one Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra,  an edgeedge with one Li(3)O5 square pyramid,  an edgeedge with one Mn(1)O5 square pyramid, and  an edgeedge with one Li(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-85°. The Li(3)-O(2) bond length is 2.17 Å. The Li(3)-O(4) bond length is 2.03 Å. The Li(3)-O(6) bond length is 2.04 Å. There is one shorter (2.08 Å) and one longer (2.19 Å) Li(3)-O(3) bond length. In the fourth Li site, Li(4) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(1)O5 square pyramids, and edges with two equivalent Li(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 49-67°. Both Li(4)-O(1) bond lengths are 1.94 Å. Both Li(4)-O(3) bond lengths are 1.98 Å. In the fifth Li site, Li(5) is bonded in a 3-coordinate geometry to one O(4), one O(5), and two equivalent O(2) atoms. The Li(5)-O(4) bond length is 1.92 Å. The Li(5)-O(5) bond length is 1.83 Å. There is one shorter (1.99 Å) and one longer (2.41 Å) Li(5)-O(2) bond length. In the sixth Li site, Li(6) is bonded in a 4-coordinate geometry to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. Both Li(6)-O(4) bond lengths are 2.49 Å. Both Li(6)-O(5) bond lengths are 2.03 Å. Both Li(6)-O(6) bond lengths are 2.03 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with three equivalent Li(3)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Li(3)O5 square pyramid, and  an edgeedge with one Mn(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 84-87°. The Mn(1)-O(1) bond length is 2.23 Å. The Mn(1)-O(3) bond length is 2.00 Å. The Mn(1)-O(4) bond length is 1.95 Å. There is one shorter (1.97 Å) and one longer (2.00 Å) Mn(1)-O(2) bond length. In the second Mn site, Mn(2) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Li(3)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Li(3)O5 square pyramids, and edges with two equivalent Mn(1)O5 square pyramids. Both Mn(2)-O(3) bond lengths are 1.98 Å. Both Mn(2)-O(4) bond lengths are 1.96 Å. Both Mn(2)-O(5) bond lengths are 2.43 Å. In the third Mn site, Mn(3) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(6) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Li(3)O5 square pyramid, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Li(4)O4 tetrahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(1)O5 square pyramid, and edges with two equivalent Li(3)O5 square pyramids. The Mn(3)-O(1) bond length is 1.92 Å. The Mn(3)-O(2) bond length is 2.62 Å. The Mn(3)-O(3) bond length is 2.57 Å. The Mn(3)-O(5) bond length is 1.91 Å. There is one shorter (1.96 Å) and one longer (1.97 Å) Mn(3)-O(6) bond length. There are six inequivalent O sites. In the first O site, O(6) is bonded to one Li(2), one Li(3), one Li(6), and two equivalent Mn(3) atoms to form OLi3Mn2 square pyramids that share  a cornercorner with one O(5)Li4Mn2 octahedra, corners with two equivalent O(1)Li4Mn2 octahedra,  a cornercorner with one O(6)Li3Mn2 square pyramid,  an edgeedge with one O(1)Li4Mn2 octahedra, edges with two equivalent O(5)Li4Mn2 octahedra, and  an edgeedge with one O(6)Li3Mn2 square pyramid. The corner-sharing octahedral tilt angles range from 8-11°. In the second O site, O(1) is bonded to one Li(1), one Li(4), two equivalent Li(2), one Mn(1), and one Mn(3) atom to form distorted OLi4Mn2 octahedra that share  a cornercorner with one O(1)Li4Mn2 octahedra,  a cornercorner with one O(5)Li4Mn2 octahedra, corners with two equivalent O(6)Li3Mn2 square pyramids, edges with two equivalent O(5)Li4Mn2 octahedra,  an edgeedge with one O(6)Li3Mn2 square pyramid, and  a faceface with one O(1)Li4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-11°. In the third O site, O(2) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(5), one Mn(3), and two equivalent Mn(1) atoms. In the fourth O site, O(3) is bonded in a 7-coordinate geometry to one Li(2), one Li(4), two equivalent Li(3), one Mn(1), one Mn(2), and one Mn(3) atom. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to one Li(1), one Li(3), one Li(5), one Li(6), one Mn(1), and one Mn(2) atom. In the sixth O site, O(5) is bonded to one Li(1), one Li(2), one Li(5), one Li(6), one Mn(2), and one Mn(3) atom to form distorted OLi4Mn2 octahedra that share  a cornercorner with one O(1)Li4Mn2 octahedra, corners with three equivalent O(5)Li4Mn2 octahedra,  a cornercorner with one O(6)Li3Mn2 square pyramid, edges with two equivalent O(1)Li4Mn2 octahedra, and edges with two equivalent O(6)Li3Mn2 square pyramids. The corner-sharing octahedral tilt angles range from 0-11°.