Materials Data on Sr3Co2O9 by Materials Project
Sr3Co2O9 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.81 Å. In the second Sr site, Sr is bonded to twelve O atoms to form a mixture of face and corner-sharing SrO12 cuboctahedra. There are a spread of Sr–O bond distances ranging from 2.72–2.94 Å. Co is bonded in a 5-coordinate geometry to six O atoms. There are a spread of Co–O bond distances ranging from 1.90–2.59 Å. There are five inequivalent O sites. In the first O site, O is bonded in a 6-coordinate geometry to four Sr and two equivalent Co atoms. In the second O site, O is bonded to four equivalent Sr, one Co, and one O atom to form a mixture of distorted edge and corner-sharing OSr4CoO octahedra. The corner-sharing octahedra tilt angles range from 1–25°. The O–O bond length is 1.36 Å. In the third O site, O is bonded in a linear geometry to one Sr and one O atom. In the fourth O site, O is bonded in a 6-coordinate geometry to four Sr and two equivalent Co atoms. In the fifth O site, O is bonded to four equivalent Sr and two equivalent Co atoms to form a mixture of distorted edge and corner-sharing OSr4Co2 octahedra. The corner-sharing octahedra tilt angles range from 0–1°.