Materials Data on Li2(FeO2)5 by Materials Project

Li2(FeO2)5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li is bonded to six O atoms to form distorted LiO6 octahedra that share corners with five FeO6 octahedra, edges with two equivalent LiO6 octahedra, and edges with five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 6–25°. There are a spread of Li–O bond distances ranging from 2.04–2.36 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form distorted FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with two equivalent LiO6 octahedra, edges with three equivalent LiO6 octahedra, and edges with five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 10–25°. There are a spread of Fe–O bond distances ranging from 1.80–2.25 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four FeO6 octahedra, edges with two equivalent LiO6 octahedra, and edges with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 10–13°. There are a spread of Fe–O bond distances ranging from 1.94–2.09 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with three equivalent LiO6 octahedra, an edgeedge with one LiO6 octahedra, and edges with seven FeO6 octahedra. The corner-sharing octahedra tilt angles range from 6–23°. There are a spread of Fe–O bond distances ranging from 1.94–2.16 Å. There are five inequivalent O sites. In the first O site, O is bonded to one Li and four Fe atoms to form a mixture of edge and corner-sharing OLiFe4 square pyramids. In the second O site, O is bonded in a rectangular see-saw-like geometry to two equivalent Li and two equivalent Fe atoms. In the third O site, O is bonded in a see-saw-like geometry to four Fe atoms. In the fourth O site, O is bonded in a distorted see-saw-like geometry to one Li and three Fe atoms. In the fifth O site, O is bonded in a rectangular see-saw-like geometry to two equivalent Li and two Fe atoms.