DOE OSTI2020
Sr3Co2O6 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Sr2+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–2.69 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six equivalent O2- atoms to form face-sharing CoO6 octahedra. All Co–O bond lengths are 1.96 Å. In the second Co3+ site, Co3+ is bonded to six equivalent O2- atoms to form distorted face-sharing CoO6 pentagonal pyramids. All Co–O bond lengths are 2.08 Å. O2- is bonded to four equivalent Sr2+ and two Co3+ atoms to form a mixture of distorted edge, face, and corner-sharing OSr4Co2 octahedra. The corner-sharing octahedra tilt angles range from 0–64°.