Materials Data on LiCr(FeO2)4 by Materials Project
LiCr(FeO2)4 is Spinel-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with six equivalent FeO4 tetrahedra, edges with two equivalent CrO6 octahedra, and edges with four equivalent FeO6 octahedra. All Li–O bond lengths are 2.11 Å. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six equivalent FeO4 tetrahedra, edges with two equivalent LiO6 octahedra, and edges with four equivalent FeO6 octahedra. There are four shorter (2.03 Å) and two longer (2.05 Å) Cr–O bond lengths. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent LiO6 octahedra, corners with three equivalent CrO6 octahedra, and corners with six equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 56–57°. There is three shorter (1.91 Å) and one longer (1.98 Å) Fe–O bond length. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent FeO4 tetrahedra, edges with two equivalent LiO6 octahedra, edges with two equivalent CrO6 octahedra, and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.03–2.08 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Cr3+ and three Fe3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+ and three Fe3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+, one Cr3+, and two Fe3+ atoms.