Li3Mn4O8 crystallizes in the monoclinic C2/m space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(3) and four equivalent O(5) atoms to form LiO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(5)O6 octahedra, and edges with four equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-14°. In the second Li site, Li(2) is bonded to two equivalent O(4) and four equivalent O(6) atoms to form LiO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. In the third Li site, Li(3) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(5) atoms. In the fourth Li site, Li(4) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(4), and two equivalent O(6) atoms. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted MnO6 octahedra that share corners with three equivalent Li(1)O6 octahedra, corners with three equivalent Li(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(5)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form MnO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the third Mn site, Mn(3) is bonded to two equivalent O(2) and four equivalent O(6) atoms to form MnO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Mn(5)O6 octahedra. In the fifth Mn site, Mn(5) is bonded to two equivalent O(1) and four equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(4)O6 octahedra. There are six inequivalent O sites. In the first O site, O(3) is bonded to one Li(1), one Li(3), one Mn(1), and two equivalent Mn(4) atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 square pyramids. In the second O site, O(4) is bonded to one Li(2), one Li(4), one Mn(1), and two equivalent Mn(2) atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 square pyramids. In the third O site, O(5) is bonded to one Li(1), one Li(3), one Mn(1), one Mn(4), and one Mn(5) atom to form a mixture of distorted edge and corner-sharing OLi2Mn3 trigonal bipyramids. In the fourth O site, O(6) is bonded to one Li(2), one Li(4), one Mn(1), one Mn(2), and one Mn(3) atom to form a mixture of edge and corner-sharing OLi2Mn3 trigonal bipyramids. In the fifth O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Li(4), one Mn(5), and two equivalent Mn(4) atoms. In the sixth O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Mn(3), and two equivalent Mn(2) atoms.
Li3Mn4O8 crystallizes in the monoclinic C2/m space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(3) and four equivalent O(5) atoms to form LiO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(5)O6 octahedra, and edges with four equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-14°. Both Li(1)-O(3) bond lengths are 2.13 Å. All Li(1)-O(5) bond lengths are 2.07 Å. In the second Li site, Li(2) is bonded to two equivalent O(4) and four equivalent O(6) atoms to form LiO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. Both Li(2)-O(4) bond lengths are 2.13 Å. All Li(2)-O(6) bond lengths are 2.06 Å. In the third Li site, Li(3) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(5) atoms. The Li(3)-O(2) bond length is 1.91 Å. The Li(3)-O(3) bond length is 2.25 Å. Both Li(3)-O(5) bond lengths are 2.06 Å. In the fourth Li site, Li(4) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(4), and two equivalent O(6) atoms. The Li(4)-O(1) bond length is 1.90 Å. The Li(4)-O(4) bond length is 2.25 Å. Both Li(4)-O(6) bond lengths are 2.07 Å. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted MnO6 octahedra that share corners with three equivalent Li(1)O6 octahedra, corners with three equivalent Li(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Mn(5)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. The Mn(1)-O(3) bond length is 2.24 Å. The Mn(1)-O(4) bond length is 2.22 Å. Both Mn(1)-O(5) bond lengths are 2.21 Å. Both Mn(1)-O(6) bond lengths are 2.20 Å. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form MnO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. Both Mn(2)-O(2) bond lengths are 1.93 Å. Both Mn(2)-O(4) bond lengths are 1.97 Å. Both Mn(2)-O(6) bond lengths are 1.96 Å. In the third Mn site, Mn(3) is bonded to two equivalent O(2) and four equivalent O(6) atoms to form MnO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. Both Mn(3)-O(2) bond lengths are 2.19 Å. All Mn(3)-O(6) bond lengths are 1.98 Å. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Mn(5)O6 octahedra. Both Mn(4)-O(1) bond lengths are 1.93 Å. Both Mn(4)-O(3) bond lengths are 1.97 Å. Both Mn(4)-O(5) bond lengths are 1.96 Å. In the fifth Mn site, Mn(5) is bonded to two equivalent O(1) and four equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(4)O6 octahedra. Both Mn(5)-O(1) bond lengths are 2.19 Å. All Mn(5)-O(5) bond lengths are 1.98 Å. There are six inequivalent O sites. In the first O site, O(3) is bonded to one Li(1), one Li(3), one Mn(1), and two equivalent Mn(4) atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 square pyramids. In the second O site, O(4) is bonded to one Li(2), one Li(4), one Mn(1), and two equivalent Mn(2) atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 square pyramids. In the third O site, O(5) is bonded to one Li(1), one Li(3), one Mn(1), one Mn(4), and one Mn(5) atom to form a mixture of distorted edge and corner-sharing OLi2Mn3 trigonal bipyramids. In the fourth O site, O(6) is bonded to one Li(2), one Li(4), one Mn(1), one Mn(2), and one Mn(3) atom to form a mixture of edge and corner-sharing OLi2Mn3 trigonal bipyramids. In the fifth O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Li(4), one Mn(5), and two equivalent Mn(4) atoms. In the sixth O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Mn(3), and two equivalent Mn(2) atoms.