Materials Data on CaIrO3 by Materials Project

Abstract

CaIrO3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.43 Å. Ir4+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing IrO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are two shorter (1.90 Å) and four longer (2.31 Å) Ir–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ca2+ and four equivalent Ir4+ atoms to form OCaIr4 square pyramids that share corners with four equivalent OCaIr4 square pyramids, corners with six equivalent OCa3Ir tetrahedra, edges with four equivalent OCaIr4 square pyramids, and edges with four equivalent OCa3Ir tetrahedra. In the second O2- site, O2- is bonded to three equivalent Ca2+ and one Ir4+ atom to form distorted OCa3Ir tetrahedra that share corners with three equivalent OCaIr4 square pyramids, corners with ten equivalent OCa3Ir tetrahedra, edges with two equivalent OCaIr4 square pyramids, and edges with three equivalent OCa3Ir tetrahedra.