Li3Mn3FeO8 crystallizes in the hexagonal P6_3mc space group. Li(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with seven equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and  a faceface with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-48°. Mn(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with seven equivalent Li(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with four equivalent Mn(1)O6 octahedra, and  a faceface with one Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-53°. Fe(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with six equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Li(1) and three equivalent Mn(1) atoms to form edge-sharing OLi3Mn3 octahedra. In the second O site, O(2) is bonded to two equivalent Li(1), two equivalent Mn(1), and one Fe(1) atom to form distorted OLi2Mn2Fe trigonal bipyramids that share corners with seven equivalent O(3)Li2Mn2Fe square pyramids, corners with two equivalent O(2)Li2Mn2Fe trigonal bipyramids, edges with two equivalent O(1)Li3Mn3 octahedra, edges with two equivalent O(3)Li2Mn2Fe square pyramids, and edges with two equivalent O(2)Li2Mn2Fe trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Li(1), two equivalent Mn(1), and one Fe(1) atom to form OLi2Mn2Fe square pyramids that share corners with two equivalent O(3)Li2Mn2Fe square pyramids, corners with seven equivalent O(2)Li2Mn2Fe trigonal bipyramids, edges with two equivalent O(1)Li3Mn3 octahedra, edges with two equivalent O(3)Li2Mn2Fe square pyramids, and edges with two equivalent O(2)Li2Mn2Fe trigonal bipyramids. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to three equivalent Li(1) and three equivalent Mn(1) atoms.
Li3Mn3FeO8 crystallizes in the hexagonal P6_3mc space group. Li(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with seven equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and  a faceface with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-48°. The Li(1)-O(1) bond length is 2.04 Å. The Li(1)-O(4) bond length is 2.22 Å. Both Li(1)-O(2) bond lengths are 2.17 Å. Both Li(1)-O(3) bond lengths are 2.02 Å. Mn(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with seven equivalent Li(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with four equivalent Mn(1)O6 octahedra, and  a faceface with one Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-53°. The Mn(1)-O(1) bond length is 1.94 Å. The Mn(1)-O(4) bond length is 1.98 Å. Both Mn(1)-O(2) bond lengths are 1.95 Å. Both Mn(1)-O(3) bond lengths are 1.96 Å. Fe(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with six equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Fe(1)-O(2) bond lengths are 2.01 Å. All Fe(1)-O(3) bond lengths are 2.16 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Li(1) and three equivalent Mn(1) atoms to form edge-sharing OLi3Mn3 octahedra. In the second O site, O(2) is bonded to two equivalent Li(1), two equivalent Mn(1), and one Fe(1) atom to form distorted OLi2Mn2Fe trigonal bipyramids that share corners with seven equivalent O(3)Li2Mn2Fe square pyramids, corners with two equivalent O(2)Li2Mn2Fe trigonal bipyramids, edges with two equivalent O(1)Li3Mn3 octahedra, edges with two equivalent O(3)Li2Mn2Fe square pyramids, and edges with two equivalent O(2)Li2Mn2Fe trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Li(1), two equivalent Mn(1), and one Fe(1) atom to form OLi2Mn2Fe square pyramids that share corners with two equivalent O(3)Li2Mn2Fe square pyramids, corners with seven equivalent O(2)Li2Mn2Fe trigonal bipyramids, edges with two equivalent O(1)Li3Mn3 octahedra, edges with two equivalent O(3)Li2Mn2Fe square pyramids, and edges with two equivalent O(2)Li2Mn2Fe trigonal bipyramids. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to three equivalent Li(1) and three equivalent Mn(1) atoms.