LiMn8O16 crystallizes in the tetragonal P-4m2 space group. Li(1) is bonded to four equivalent O(2) 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°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Li(1)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(2), two equivalent O(1), and three equivalent O(3) atoms to form MnO6 octahedra that share  a cornercorner with one Li(1)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 in a distorted T-shaped geometry to one Mn(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded to one Li(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OLiMn3 trigonal pyramids. In the third O site, O(3) is bonded in a distorted T-shaped geometry to three equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to three equivalent Mn(1) atoms.
LiMn8O16 crystallizes in the tetragonal P-4m2 space group. Li(1) is bonded to four equivalent O(2) 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(2) bond lengths are 1.98 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The Mn(1)-O(1) bond length is 1.95 Å. Both Mn(1)-O(2) bond lengths are 1.98 Å. There is one shorter (1.95 Å) and two longer (1.96 Å) Mn(1)-O(4) bond lengths. In the second Mn site, Mn(2) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form MnO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The Mn(2)-O(2) bond length is 1.97 Å. Both Mn(2)-O(1) bond lengths are 1.95 Å. There is one shorter (1.95 Å) and two longer (1.96 Å) Mn(2)-O(3) bond lengths. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mn(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded to one Li(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OLiMn3 trigonal pyramids. In the third O site, O(3) is bonded in a distorted T-shaped geometry to three equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to three equivalent Mn(1) atoms.