Li2FeO2 crystallizes in the monoclinic Pc space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra,  an edgeedge with one Fe(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Li(4)O4 tetrahedra, and edges with two equivalent Li(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-57°. In the second Li site, Li(2) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Li(3)O4 tetrahedra, and edges with two equivalent Li(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. In the third Li site, Li(3) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with four equivalent Li(4)O4 tetrahedra,  an edgeedge with one Fe(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Li(2)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-57°. In the fourth Li site, Li(4) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(3)O4 tetrahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Li(1)O4 tetrahedra, and edges with two equivalent Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO6 octahedra that share corners with three equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, corners with three equivalent Li(3)O4 tetrahedra, corners with three equivalent Li(4)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Li(2)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, and edges with two equivalent Li(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share corners with three equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, corners with three equivalent Li(3)O4 tetrahedra, corners with three equivalent Li(4)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Li(1)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, and edges with two equivalent Li(4)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to one Li(1), one Li(4), two equivalent Li(3), one Fe(2), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(4), one Fe(1), and two equivalent Fe(2) atoms. In the third O site, O(3) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(1), one Fe(2), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a 7-coordinate geometry to one Li(1), one Li(4), two equivalent Li(2), one Fe(1), and two equivalent Fe(2) atoms.
Li2FeO2 crystallizes in the monoclinic Pc space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra,  an edgeedge with one Fe(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Li(4)O4 tetrahedra, and edges with two equivalent Li(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-57°. The Li(1)-O(1) bond length is 2.06 Å. The Li(1)-O(4) bond length is 1.94 Å. Both Li(1)-O(3) bond lengths are 1.96 Å. In the second Li site, Li(2) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Li(3)O4 tetrahedra, and edges with two equivalent Li(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. The Li(2)-O(2) bond length is 2.05 Å. The Li(2)-O(3) bond length is 1.94 Å. There is one shorter (1.95 Å) and one longer (1.97 Å) Li(2)-O(4) bond length. In the third Li site, Li(3) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with four equivalent Li(4)O4 tetrahedra,  an edgeedge with one Fe(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Li(2)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-57°. The Li(3)-O(2) bond length is 1.96 Å. The Li(3)-O(3) bond length is 2.06 Å. Both Li(3)-O(1) bond lengths are 1.95 Å. In the fourth Li site, Li(4) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(3)O4 tetrahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Li(1)O4 tetrahedra, and edges with two equivalent Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. The Li(4)-O(1) bond length is 1.96 Å. The Li(4)-O(4) bond length is 2.06 Å. There is one shorter (1.94 Å) and one longer (1.95 Å) Li(4)-O(2) bond length. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO6 octahedra that share corners with three equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, corners with three equivalent Li(3)O4 tetrahedra, corners with three equivalent Li(4)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Li(2)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, and edges with two equivalent Li(3)O4 tetrahedra. The Fe(1)-O(2) bond length is 2.26 Å. The Fe(1)-O(4) bond length is 2.13 Å. There is one shorter (2.13 Å) and one longer (2.34 Å) Fe(1)-O(1) bond length. There is one shorter (2.26 Å) and one longer (2.34 Å) Fe(1)-O(3) bond length. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share corners with three equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, corners with three equivalent Li(3)O4 tetrahedra, corners with three equivalent Li(4)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Li(1)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, and edges with two equivalent Li(4)O4 tetrahedra. The Fe(2)-O(1) bond length is 2.26 Å. The Fe(2)-O(3) bond length is 2.13 Å. There is one shorter (2.12 Å) and one longer (2.35 Å) Fe(2)-O(2) bond length. There is one shorter (2.25 Å) and one longer (2.33 Å) Fe(2)-O(4) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to one Li(1), one Li(4), two equivalent Li(3), one Fe(2), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(4), one Fe(1), and two equivalent Fe(2) atoms. In the third O site, O(3) is bonded in a 7-coordinate geometry to one Li(2), one Li(3), two equivalent Li(1), one Fe(2), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a 7-coordinate geometry to one Li(1), one Li(4), two equivalent Li(2), one Fe(1), and two equivalent Fe(2) atoms.