Materials Data on BaSr4(FeO2)5 by Materials Project
BaSr4(FeO2)5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Ba–O bond lengths are 2.82 Å. There are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.65 Å) and four longer (2.69 Å) Sr–O bond lengths. In the second Sr2+ site, Sr2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.68 Å) and four longer (2.69 Å) Sr–O bond lengths. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Fe–O bond lengths are 2.04 Å. In the second Fe2+ site, Fe2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Fe–O bond lengths are 2.04 Å. In the third Fe2+ site, Fe2+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Fe–O bond lengths are 2.04 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ba2+, two equivalent Sr2+, and two equivalent Fe2+ atoms to form a mixture of distorted edge, corner, and face-sharing OBa2Sr2Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–65°. In the second O2- site, O2- is bonded to four Sr2+ and two equivalent Fe2+ atoms to form OSr4Fe2 octahedra that share corners with fourteen OBa2Sr2Fe2 octahedra, edges with four OBa2Sr2Fe2 octahedra, and faces with four equivalent OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–65°. In the third O2- site, O2- is bonded to four equivalent Sr2+ and two equivalent Fe2+ atoms to form a mixture of edge, corner, and face-sharing OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–65°.