Materials Data on Fe3(OF)2 by Materials Project

Abstract

Fe3(OF)2 crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to two equivalent O2- and two equivalent F1- atoms to form FeO2F2 tetrahedra that share corners with two equivalent FeO2F4 octahedra and corners with two equivalent FeO2F2 tetrahedra. The corner-sharing octahedral tilt angles are 73°. Both Fe–O bond lengths are 1.97 Å. Both Fe–F bond lengths are 2.15 Å. In the second Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to four equivalent O2- and two F1- atoms. All Fe–O bond lengths are 2.18 Å. There are one shorter (2.08 Å) and one longer (2.50 Å) Fe–F bond lengths. In the third Fe2+ site, Fe2+ is bonded to two equivalent O2- and four equivalent F1- atoms to form FeO2F4 octahedra that share corners with four equivalent FeO2F4 octahedra, corners with two equivalent FeO2F2 tetrahedra, and edges with four equivalent FeO2F4 octahedra. The corner-sharing octahedral tilt angles are 4°. Both Fe–O bond lengths are 1.99 Å. All Fe–F bond lengths are 2.28 Å. O2- is bonded to four Fe2+ atoms to form OFe4 tetrahedra that share corners with two equivalent FFe5 square pyramids, corners with six equivalent OFe4 tetrahedra, edges with two equivalent FFe5 square pyramids, and an edgeedge with one OFe4 tetrahedra. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to three Fe2+ atoms. In the second F1- site, F1- is bonded to five Fe2+ atoms to form FFe5 square pyramids that share corners with four equivalent FFe5 square pyramids, corners with four equivalent OFe4 tetrahedra, edges with four equivalent FFe5 square pyramids, and edges with four equivalent OFe4 tetrahedra.