Materials Data on Fe4O3F5 by Materials Project

Fe4O3F5 is zeta iron carbide-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent Fe+2.75+ sites. In the first Fe+2.75+ site, Fe+2.75+ is bonded to two equivalent O2- and four F1- atoms to form FeO2F4 octahedra that share corners with eight FeO2F4 octahedra and edges with two equivalent FeO3F3 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. Both Fe–O bond lengths are 2.07 Å. There are two shorter (2.17 Å) and two longer (2.19 Å) Fe–F bond lengths. In the second Fe+2.75+ site, Fe+2.75+ is bonded to two equivalent O2- and four F1- atoms to form FeO2F4 octahedra that share corners with eight FeO2F4 octahedra and edges with two equivalent FeO3F3 octahedra. The corner-sharing octahedra tilt angles range from 40–53°. Both Fe–O bond lengths are 1.97 Å. There are two shorter (2.02 Å) and two longer (2.05 Å) Fe–F bond lengths. In the third Fe+2.75+ site, Fe+2.75+ is bonded to three O2- and three F1- atoms to form a mixture of distorted corner and edge-sharing FeO3F3 octahedra. The corner-sharing octahedra tilt angles range from 40–57°. There is two shorter (1.91 Å) and one longer (1.96 Å) Fe–O bond length. There are a spread of Fe–F bond distances ranging from 2.11–2.52 Å. In the fourth Fe+2.75+ site, Fe+2.75+ is bonded to two equivalent O2- and four F1- atoms to form a mixture of corner and edge-sharing FeO2F4 octahedra. The corner-sharing octahedra tilt angles range from 45–53°. Both Fe–O bond lengths are 2.05 Å. There are two shorter (2.08 Å) and two longer (2.19 Å) Fe–F bond lengths. In the fifth Fe+2.75+ site, Fe+2.75+ is bonded to two O2- and four F1- atoms to form a mixture of corner and edge-sharing FeO2F4 octahedra. The corner-sharing octahedra tilt angles range from 40–57°. There is one shorter (1.89 Å) and one longer (1.94 Å) Fe–O bond length. There are a spread of Fe–F bond distances ranging from 2.03–2.11 Å. In the sixth Fe+2.75+ site, Fe+2.75+ is bonded to two equivalent O2- and four F1- atoms to form a mixture of corner and edge-sharing FeO2F4 octahedra. The corner-sharing octahedra tilt angles range from 49–55°. Both Fe–O bond lengths are 1.95 Å. There are two shorter (2.06 Å) and two longer (2.07 Å) Fe–F bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three Fe+2.75+ atoms. In the second O2- site, O2- is bonded in a trigonal planar geometry to three Fe+2.75+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Fe+2.75+ atoms. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to three Fe+2.75+ atoms. In the second F1- site, F1- is bonded in a 3-coordinate geometry to three Fe+2.75+ atoms. In the third F1- site, F1- is bonded in a 3-coordinate geometry to three Fe+2.75+ atoms. In the fourth F1- site, F1- is bonded in a 3-coordinate geometry to three Fe+2.75+ atoms. In the fifth F1- site, F1- is bonded in a 3-coordinate geometry to three Fe+2.75+ atoms.