Materials Data on Ti(FeO2)4 by Materials Project
Ti(FeO2)4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six equivalent FeO4 tetrahedra and edges with four equivalent FeO6 octahedra. There are four shorter (1.97 Å) and two longer (2.04 Å) Ti–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 TiO6 octahedra and corners with six equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–58°. There are a spread of Fe–O bond distances ranging from 1.90–1.99 Å. 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 TiO6 octahedra, and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.09 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ti4+ and two Fe3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Fe3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ti4+ and three Fe3+ atoms.