Materials Data on Fe25O32 by Materials Project

Abstract

Fe25O32 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are fifteen inequivalent Fe+2.56+ sites. In the first Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of distorted edge, corner, and face-sharing FeO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 1–9°. There are two shorter (2.12 Å) and four longer (2.20 Å) Fe–O bond lengths. In the second Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Fe–O bond distances ranging from 2.02–2.10 Å. In the third Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Fe–O bond distances ranging from 2.03–2.07 Å. In the fourth Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.03 Å) and four longer (2.05 Å) Fe–O bond lengths. In the fifth Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Fe–O bond distances ranging from 2.03–2.06 Å. In the sixth Fe+2.56+ site, Fe+2.56+ is bonded in a 5-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.00–2.75 Å. In the seventh Fe+2.56+ site, Fe+2.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.05–2.41 Å. In the eighth Fe+2.56+ site, Fe+2.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.13–2.32 Å. In the ninth Fe+2.56+ site, Fe+2.56+ is bonded in a 6-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.12–2.66 Å. In the tenth Fe+2.56+ site, Fe+2.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.10–2.45 Å. In the eleventh Fe+2.56+ site, Fe+2.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.19–2.70 Å. In the twelfth Fe+2.56+ site, Fe+2.56+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.20 Å) and four longer (2.22 Å) Fe–O bond lengths. In the thirteenth Fe+2.56+ site, Fe+2.56+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Fe–O bond distances ranging from 2.20–2.65 Å. In the fourteenth Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Fe–O bond distances ranging from 1.95–2.07 Å. In the fifteenth Fe+2.56+ site, Fe+2.56+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Fe–O bond distances ranging from 1.95–2.10 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded to six Fe+2.56+ atoms to form distorted edge-sharing OFe6 octahedra. In the second O2- site, O2- is bonded in a 5-coordinate geometry to six Fe+2.56+ atoms. In the third O2- site, O2- is bonded in a square co-planar geometry to four Fe+2.56+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Fe+2.56+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to six Fe+2.56+ atoms. In the sixth O2- site, O2- is bonded in a distorted square co-planar geometry to five Fe+2.56+ atoms. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the tenth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the twelfth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the thirteenth O2- site, O2- is bonded to six Fe+2.56+ atoms to form distorted OFe6 pentagonal pyramids that share corners with four OFe5 trigonal bipyramids, edges with two OFe5 trigonal bipyramids, and faces with two equivalent OFe6 pentagonal pyramids. In the fourteenth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the fifteenth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the sixteenth O2- site, O2- is bonded to five Fe+2.56+ atoms to form distorted OFe5 trigonal bipyramids that share corners with two equivalent OFe6 pentagonal pyramids, an edgeedge with one OFe6 pentagonal pyramid, and edges with two equivalent OFe5 trigonal bipyramids. In the seventeenth O2- site, O2- is bonded in a 5-coordinate geometry to five Fe+2.56+ atoms. In the eighteenth O2- site, O2- is bonded to five Fe+2.56+ atoms to form distorted OFe5 trigonal bipyramids that share corners with two equivalent OFe6 pentagonal pyramids, a cornercorner with one OFe5 trigonal bipyramid, an edgeedge with one OFe6 pentagonal pyramid, and edges with two equivalent OFe5 trigonal bipyramids.