Materials Data on Co5CuO8 by Materials Project

Abstract

Co5CuO8 is Spinel-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Co+2.80+ sites. In the first Co+2.80+ site, Co+2.80+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent CoO4 tetrahedra, edges with two equivalent CuO6 octahedra, and edges with four equivalent CoO6 octahedra. There is four shorter (1.92 Å) and two longer (1.95 Å) Co–O bond length. In the second Co+2.80+ site, Co+2.80+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent CuO6 octahedra and corners with nine equivalent CoO6 octahedra. The corner-sharing octahedra tilt angles range from 58–62°. There is three shorter (1.94 Å) and one longer (1.98 Å) Co–O bond length. Cu2+ is bonded to six equivalent O2- atoms to form CuO6 octahedra that share corners with six equivalent CoO4 tetrahedra and edges with six equivalent CoO6 octahedra. All Cu–O bond lengths are 2.01 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Co+2.80+ and one Cu2+ atom. In the second O2- site, O2- is bonded to four Co+2.80+ atoms to form distorted corner-sharing OCo4 trigonal pyramids.