Materials Data on VFeCoO4 by Materials Project

FeCoVO4 is Spinel-derived structured and crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. V3+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with six equivalent FeO6 octahedra and corners with six equivalent CoO6 octahedra. The corner-sharing octahedra tilt angles range from 55–59°. There is two shorter (1.95 Å) and two longer (1.98 Å) V–O bond length. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent VO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four equivalent CoO6 octahedra. There are two shorter (2.05 Å) and four longer (2.06 Å) Fe–O bond lengths. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent VO4 tetrahedra, edges with two equivalent CoO6 octahedra, and edges with four equivalent FeO6 octahedra. There are four shorter (2.10 Å) and two longer (2.13 Å) Co–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one V3+, one Fe3+, and two equivalent Co2+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one V3+, two equivalent Fe3+, and one Co2+ atom.