Materials Data on Ca7Ni(IrO6)2 by Materials Project
Ca7Ni(IrO6)2 crystallizes in the trigonal R32 space group. The structure is three-dimensional. there are three inequivalent Ca2+ sites. In the first 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 2.32–2.79 Å. In the second 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 2.41–2.72 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Ca–O bond lengths are 2.33 Å. Ir4+ is bonded to six O2- atoms to form IrO6 octahedra that share a faceface with one NiO6 pentagonal pyramid. All Ir–O bond lengths are 2.04 Å. Ni2+ is bonded to six equivalent O2- atoms to form distorted NiO6 pentagonal pyramids that share faces with two equivalent IrO6 octahedra. All Ni–O bond lengths are 2.21 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Ca2+ and one Ir4+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to four Ca2+, one Ir4+, and one Ni2+ atom.