Li3Mn8O16 is beta indium sulfide-derived structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to four equivalent O(4) atoms to form LiO4 tetrahedra that share corners with four equivalent Mn(2)O6 octahedra and corners with eight equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 59°. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-61°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), two equivalent O(4), and three equivalent O(1) atoms to form MnO6 octahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(3), and three equivalent O(2) atoms to form MnO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(2) and three equivalent Mn(1) atoms to form a mixture of distorted edge and corner-sharing OLiMn3 trigonal pyramids. In the second O site, O(2) is bonded to one Li(2) and three equivalent Mn(2) atoms to form a mixture of distorted edge and corner-sharing OLiMn3 tetrahedra. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Li(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of distorted edge and corner-sharing OLiMn3 trigonal pyramids.
Li3Mn8O16 is beta indium sulfide-derived structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to four equivalent O(4) atoms to form LiO4 tetrahedra that share corners with four equivalent Mn(2)O6 octahedra and corners with eight equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 59°. All Li(1)-O(4) bond lengths are 1.98 Å. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-61°. Both Li(2)-O(1) bond lengths are 2.01 Å. Both Li(2)-O(2) bond lengths are 2.02 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), two equivalent O(4), and three equivalent O(1) atoms to form MnO6 octahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The Mn(1)-O(3) bond length is 1.96 Å. Both Mn(1)-O(4) bond lengths are 2.00 Å. There is one shorter (1.94 Å) and two longer (2.02 Å) Mn(1)-O(1) bond lengths. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(3), and three equivalent O(2) atoms to form MnO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The Mn(2)-O(4) bond length is 1.98 Å. Both Mn(2)-O(3) bond lengths are 1.96 Å. There are two shorter (1.98 Å) and one longer (2.03 Å) Mn(2)-O(2) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(2) and three equivalent Mn(1) atoms to form a mixture of distorted edge and corner-sharing OLiMn3 trigonal pyramids. In the second O site, O(2) is bonded to one Li(2) and three equivalent Mn(2) atoms to form a mixture of distorted edge and corner-sharing OLiMn3 tetrahedra. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Li(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of distorted edge and corner-sharing OLiMn3 trigonal pyramids.