Li(FeO2)8 crystallizes in the monoclinic P2 space group. Li(1) is bonded to two equivalent O(4) and two equivalent O(6) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 62-66°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Fe(4)O6 octahedra,  a cornercorner with one Li(1)O4 trigonal pyramid, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and  an edgeedge with one Li(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 47-49°. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), two equivalent O(7), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. In the third Fe site, Fe(3) is bonded to one O(5), one O(8), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. In the fourth Fe site, Fe(4) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Li(1)O4 trigonal pyramid, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and  an edgeedge with one Li(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 47-49°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Fe(2) and two equivalent Fe(4) atoms. In the fourth O site, O(4) is bonded to one Li(1), one Fe(1), and two equivalent Fe(4) atoms to form distorted corner-sharing OLiFe3 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Fe(3) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Li(1), one Fe(4), and two equivalent Fe(1) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Fe(4) and two equivalent Fe(2) atoms. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms.
Li(FeO2)8 crystallizes in the monoclinic P2 space group. Li(1) is bonded to two equivalent O(4) and two equivalent O(6) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 62-66°. Both Li(1)-O(4) bond lengths are 1.88 Å. Both Li(1)-O(6) bond lengths are 1.89 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Fe(4)O6 octahedra,  a cornercorner with one Li(1)O4 trigonal pyramid, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and  an edgeedge with one Li(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 47-49°. The Fe(1)-O(1) bond length is 2.05 Å. The Fe(1)-O(4) bond length is 2.12 Å. There is one shorter (1.92 Å) and one longer (1.94 Å) Fe(1)-O(5) bond length. There is one shorter (1.99 Å) and one longer (2.01 Å) Fe(1)-O(6) bond length. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), two equivalent O(7), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. The Fe(2)-O(2) bond length is 1.98 Å. The Fe(2)-O(3) bond length is 2.05 Å. There is one shorter (1.94 Å) and one longer (1.95 Å) Fe(2)-O(7) bond length. There is one shorter (1.94 Å) and one longer (1.95 Å) Fe(2)-O(8) bond length. In the third Fe site, Fe(3) is bonded to one O(5), one O(8), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. The Fe(3)-O(5) bond length is 2.05 Å. The Fe(3)-O(8) bond length is 1.97 Å. There is one shorter (1.94 Å) and one longer (1.95 Å) Fe(3)-O(1) bond length. There is one shorter (1.94 Å) and one longer (1.95 Å) Fe(3)-O(2) bond length. In the fourth Fe site, Fe(4) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Li(1)O4 trigonal pyramid, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and  an edgeedge with one Li(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 47-49°. The Fe(4)-O(6) bond length is 2.12 Å. The Fe(4)-O(7) bond length is 2.05 Å. There is one shorter (1.92 Å) and one longer (1.93 Å) Fe(4)-O(3) bond length. There is one shorter (1.98 Å) and one longer (2.00 Å) Fe(4)-O(4) bond length. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Fe(2) and two equivalent Fe(4) atoms. In the fourth O site, O(4) is bonded to one Li(1), one Fe(1), and two equivalent Fe(4) atoms to form distorted corner-sharing OLiFe3 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Fe(3) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Li(1), one Fe(4), and two equivalent Fe(1) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Fe(4) and two equivalent Fe(2) atoms. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms.