DOI: 10.17188/1708183
title: Materials Data on Sr2Fe2O5 by Materials Project

description: Sr2Fe2O5 crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are two 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 2.48–2.95 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 2.48–2.97 Å. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent FeO6 octahedra and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 7–10°. There are four shorter (2.02 Å) and two longer (2.22 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent FeO6 octahedra and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 7–10°. There are a spread of Fe–O bond distances ranging from 2.02–2.22 Å. In the third Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with two equivalent FeO6 octahedra and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 33°. There are a spread of Fe–O bond distances ranging from 1.89–1.95 Å. In the fourth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with two equivalent FeO6 octahedra and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 33°. There are a spread of Fe–O bond distances ranging from 1.89–1.95 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to four Sr2+ and two Fe3+ atoms to form distorted OSr4Fe2 octahedra that share corners with two OSr4Fe2 octahedra, corners with four OSr2Fe2 tetrahedra, edges with two OSr4Fe2 octahedra, and faces with four OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the second O2- site, O2- is bonded to two equivalent Sr2+ and two Fe3+ atoms to form distorted OSr2Fe2 tetrahedra that share corners with eight OSr4Fe2 octahedra and corners with two equivalent OSr2Fe2 tetrahedra. The corner-sharing octahedra tilt angles range from 19–80°. In the third O2- site, O2- is bonded to two equivalent Sr2+ and two Fe3+ atoms to form distorted OSr2Fe2 tetrahedra that share corners with eight OSr4Fe2 octahedra and corners with two equivalent OSr2Fe2 tetrahedra. The corner-sharing octahedra tilt angles range from 19–81°. In the fourth O2- site, O2- is bonded to four Sr2+ and two Fe3+ atoms to form distorted OSr4Fe2 octahedra that share corners with two OSr4Fe2 octahedra, corners with four OSr2Fe2 tetrahedra, edges with two OSr4Fe2 octahedra, and faces with four OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two Fe3+ atoms. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two Fe3+ atoms.