Materials Data on Sr2Ca2IrO6 by Materials Project
Sr2Ca2IrO6 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–2.82 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.79 Å. In the third Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.76 Å. There are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 pentagonal pyramids that share faces with two equivalent IrO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.34–2.39 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.33 Å) and four longer (2.35 Å) Ca–O bond lengths. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.45–2.84 Å. Ir4+ is bonded to six O2- atoms to form IrO6 octahedra that share a faceface with one CaO6 pentagonal pyramid. There are a spread of Ir–O bond distances ranging from 2.04–2.09 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to two Sr2+, three Ca2+, and one Ir4+ atom to form distorted OSr2Ca3Ir octahedra that share corners with fourteen OSr2Ca3Ir octahedra, edges with two OSr3Ca2Ir octahedra, and faces with four OSr2Ca3Ir octahedra. The corner-sharing octahedra tilt angles range from 2–65°. In the second O2- site, O2- is bonded to three Sr2+, two Ca2+, and one Ir4+ atom to form distorted OSr3Ca2Ir octahedra that share corners with twelve OSr2Ca3Ir octahedra, edges with three OSr2Ca3Ir octahedra, and faces with five OSr3Ca2Ir octahedra. The corner-sharing octahedra tilt angles range from 16–65°. In the third O2- site, O2- is bonded to three Sr2+, two Ca2+, and one Ir4+ atom to form distorted OSr3Ca2Ir octahedra that share corners with twelve OSr2Ca3Ir octahedra, edges with four OSr3Ca2Ir octahedra, and faces with four OSr2Ca3Ir octahedra. The corner-sharing octahedra tilt angles range from 1–59°. In the fourth O2- site, O2- is bonded to three Sr2+, two Ca2+, and one Ir4+ atom to form distorted OSr3Ca2Ir octahedra that share corners with thirteen OSr2Ca3Ir octahedra, edges with three OSr2Ca3Ir octahedra, and faces with four OSr3Ca2Ir octahedra. The corner-sharing octahedra tilt angles range from 2–65°. In the fifth O2- site, O2- is bonded to three Sr2+, two Ca2+, and one Ir4+ atom to form distorted OSr3Ca2Ir octahedra that share corners with thirteen OSr2Ca3Ir octahedra, edges with four OSr3Ca2Ir octahedra, and faces with three OSr2Ca3Ir octahedra. The corner-sharing octahedra tilt angles range from 1–65°. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to two Sr2+, three Ca2+, and one Ir4+ atom.