Materials Data on Sr4FeRh2O9 by Materials Project

Abstract

Sr4FeRh2O9 crystallizes in the trigonal P321 space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–3.10 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 2.41–2.91 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 2.46–2.73 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form distorted FeO6 pentagonal pyramids that share faces with two RhO6 octahedra. There are three shorter (2.07 Å) and three longer (2.13 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to six equivalent O2- atoms to form distorted FeO6 pentagonal pyramids that share faces with two equivalent RhO6 octahedra. All Fe–O bond lengths are 2.10 Å. There are three inequivalent Rh+3.50+ sites. In the first Rh+3.50+ site, Rh+3.50+ is bonded to six O2- atoms to form RhO6 octahedra that share a faceface with one RhO6 octahedra and a faceface with one FeO6 pentagonal pyramid. There are three shorter (2.00 Å) and three longer (2.11 Å) Rh–O bond lengths. In the second Rh+3.50+ site, Rh+3.50+ is bonded to six O2- atoms to form RhO6 octahedra that share a faceface with one RhO6 octahedra and a faceface with one FeO6 pentagonal pyramid. There are three shorter (2.03 Å) and three longer (2.07 Å) Rh–O bond lengths. In the third Rh+3.50+ site, Rh+3.50+ is bonded to six O2- atoms to form RhO6 octahedra that share a faceface with one RhO6 octahedra and a faceface with one FeO6 pentagonal pyramid. There are three shorter (2.03 Å) and three longer (2.09 Å) Rh–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+, one Fe3+, and one Rh+3.50+ atom. In the second O2- site, O2- is bonded to four Sr2+, one Fe3+, and one Rh+3.50+ atom to form distorted OSr4FeRh octahedra that share corners with eight OSr4FeRh octahedra, an edgeedge with one OSr4Rh2 octahedra, and faces with five OSr4FeRh octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the third O2- site, O2- is bonded to four Sr2+ and two Rh+3.50+ atoms to form a mixture of distorted corner, edge, and face-sharing OSr4Rh2 octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the fourth O2- site, O2- is bonded to four Sr2+ and two equivalent Rh+3.50+ atoms to form distorted OSr4Rh2 octahedra that share corners with eight OSr4FeRh octahedra, edges with two equivalent OSr4Rh2 octahedra, and faces with two equivalent OSr4Rh2 octahedra. The corner-sharing octahedra tilt angles range from 27–58°. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to four Sr2+, one Fe3+, and one Rh+3.50+ atom.