Li4Mn5SnO12 crystallizes in the monoclinic C2/m space group. Li(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form MnO6 octahedra that share edges with three equivalent Mn(2)O6 octahedra and edges with three equivalent Sn(1)O6 octahedra. In the third Mn site, Mn(3) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. Sn(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form SnO6 octahedra that share edges with six equivalent Mn(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), two equivalent Mn(2), and one Sn(1) atom to form distorted OLi2Mn2Sn trigonal bipyramids that share corners with two equivalent O(2)Li2Mn3 trigonal bipyramids, corners with three equivalent O(1)Li2Mn2Sn trigonal bipyramids,  an edgeedge with one O(2)Li2Mn3 trigonal bipyramid, and edges with four equivalent O(1)Li2Mn2Sn trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Li(1), one Mn(3), and two equivalent Mn(1) atoms to form distorted OLi2Mn3 trigonal bipyramids that share corners with two equivalent O(1)Li2Mn2Sn trigonal bipyramids, corners with three equivalent O(2)Li2Mn3 trigonal bipyramids,  an edgeedge with one O(1)Li2Mn2Sn trigonal bipyramid, and edges with four equivalent O(2)Li2Mn3 trigonal bipyramids. In the third O site, O(3) is bonded in a trigonal non-coplanar geometry to one Mn(3) and two equivalent Mn(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Mn(2) and one Sn(1) atom.
Li4Mn5SnO12 crystallizes in the monoclinic C2/m space group. Li(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There is one shorter (2.04 Å) and one longer (2.10 Å) Li(1)-O(1) bond length. There is one shorter (2.06 Å) and one longer (2.10 Å) Li(1)-O(2) bond length. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. Both Mn(1)-O(3) bond lengths are 1.97 Å. There are two shorter (1.95 Å) and two longer (2.18 Å) Mn(1)-O(2) bond lengths. In the second Mn site, Mn(2) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form MnO6 octahedra that share edges with three equivalent Mn(2)O6 octahedra and edges with three equivalent Sn(1)O6 octahedra. Both Mn(2)-O(4) bond lengths are 1.96 Å. There are two shorter (1.96 Å) and two longer (2.31 Å) Mn(2)-O(1) bond lengths. In the third Mn site, Mn(3) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing MnO6 octahedra. Both Mn(3)-O(3) bond lengths are 1.96 Å. All Mn(3)-O(2) bond lengths are 2.12 Å. Sn(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form SnO6 octahedra that share edges with six equivalent Mn(2)O6 octahedra. Both Sn(1)-O(4) bond lengths are 2.09 Å. All Sn(1)-O(1) bond lengths are 2.11 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), two equivalent Mn(2), and one Sn(1) atom to form distorted OLi2Mn2Sn trigonal bipyramids that share corners with two equivalent O(2)Li2Mn3 trigonal bipyramids, corners with three equivalent O(1)Li2Mn2Sn trigonal bipyramids,  an edgeedge with one O(2)Li2Mn3 trigonal bipyramid, and edges with four equivalent O(1)Li2Mn2Sn trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Li(1), one Mn(3), and two equivalent Mn(1) atoms to form distorted OLi2Mn3 trigonal bipyramids that share corners with two equivalent O(1)Li2Mn2Sn trigonal bipyramids, corners with three equivalent O(2)Li2Mn3 trigonal bipyramids,  an edgeedge with one O(1)Li2Mn2Sn trigonal bipyramid, and edges with four equivalent O(2)Li2Mn3 trigonal bipyramids. In the third O site, O(3) is bonded in a trigonal non-coplanar geometry to one Mn(3) and two equivalent Mn(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Mn(2) and one Sn(1) atom.