Materials Data on FeHO2 by Materials Project

Abstract

FeOOH crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Fe3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Fe–O bond distances ranging from 2.00–2.14 Å. H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.71 Å) H–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Fe3+ and one H1+ atom to form distorted corner-sharing OFe3H tetrahedra. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Fe3+ and one H1+ atom.