Materials Data on Sr2IrO4 by Materials Project

Abstract

Sr2IrO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.44–2.80 Å. Ir4+ is bonded to six O2- atoms to form corner-sharing IrO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.98 Å) and two longer (2.08 Å) Ir–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to five equivalent Sr2+ and one Ir4+ atom to form distorted OSr5Ir octahedra that share corners with seventeen OSr5Ir octahedra, edges with eight equivalent OSr5Ir octahedra, and faces with four equivalent OSr4Ir2 octahedra. The corner-sharing octahedra tilt angles range from 0–56°. In the second O2- site, O2- is bonded to four equivalent Sr2+ and two equivalent Ir4+ atoms to form distorted OSr4Ir2 octahedra that share corners with fourteen OSr5Ir octahedra, edges with two equivalent OSr4Ir2 octahedra, and faces with eight OSr5Ir octahedra. The corner-sharing octahedra tilt angles range from 0–56°.