Li5(FeO2)4 crystallizes in the trigonal R3m space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded in a 3-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to one O(1) and three equivalent O(2) atoms. In the third Li site, Li(3) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form LiO6 octahedra that share edges with six equivalent Fe(2)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share edges with two equivalent Li(3)O6 octahedra and edges with four equivalent Fe(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded to three equivalent Li(1) and three equivalent Fe(2) atoms to form edge-sharing OLi3Fe3 octahedra. In the second O site, O(1) is bonded in a 7-coordinate geometry to one Li(2), three equivalent Li(1), and three equivalent Fe(2) atoms. In the third O site, O(2) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and two equivalent Fe(2) atoms. In the fourth O site, O(3) is bonded to one Li(3), two equivalent Li(1), one Fe(1), and two equivalent Fe(2) atoms to form edge-sharing OLi3Fe3 octahedra.
Li5(FeO2)4 crystallizes in the trigonal R3m space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded in a 3-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. The Li(1)-O(1) bond length is 2.40 Å. The Li(1)-O(4) bond length is 1.95 Å. Both Li(1)-O(2) bond lengths are 2.30 Å. Both Li(1)-O(3) bond lengths are 2.02 Å. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to one O(1) and three equivalent O(2) atoms. The Li(2)-O(1) bond length is 1.78 Å. All Li(2)-O(2) bond lengths are 1.89 Å. In the third Li site, Li(3) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form LiO6 octahedra that share edges with six equivalent Fe(2)O6 octahedra. All Li(3)-O(2) bond lengths are 2.21 Å. All Li(3)-O(3) bond lengths are 2.11 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. All Fe(1)-O(2) bond lengths are 2.13 Å. All Fe(1)-O(3) bond lengths are 1.99 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share edges with two equivalent Li(3)O6 octahedra and edges with four equivalent Fe(2)O6 octahedra. The Fe(2)-O(1) bond length is 2.04 Å. The Fe(2)-O(4) bond length is 2.07 Å. Both Fe(2)-O(2) bond lengths are 2.07 Å. Both Fe(2)-O(3) bond lengths are 2.09 Å. There are four inequivalent O sites. In the first O site, O(4) is bonded to three equivalent Li(1) and three equivalent Fe(2) atoms to form edge-sharing OLi3Fe3 octahedra. In the second O site, O(1) is bonded in a 7-coordinate geometry to one Li(2), three equivalent Li(1), and three equivalent Fe(2) atoms. In the third O site, O(2) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and two equivalent Fe(2) atoms. In the fourth O site, O(3) is bonded to one Li(3), two equivalent Li(1), one Fe(1), and two equivalent Fe(2) atoms to form edge-sharing OLi3Fe3 octahedra.