Materials Data on Ca2Co2O5 by Materials Project

Abstract

Ca2Co2O5 crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.31–2.88 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with two equivalent CoO6 octahedra and corners with two equivalent CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. There are a spread of Co–O bond distances ranging from 1.82–1.96 Å. In the second Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with four equivalent CoO6 octahedra and corners with two equivalent CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 12°. There are a spread of Co–O bond distances ranging from 1.92–2.21 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Ca2+ and two Co3+ atoms. In the second O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Co3+ atoms to form distorted corner-sharing OCa2Co2 tetrahedra. In the third O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Ca2+ and two equivalent Co3+ atoms.