FeOOH crystallizes in the orthorhombic P2_12_12_1 space group. Fe(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 56-58°. H(1) is bonded in a single-bond geometry to one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to three equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom.
FeOOH crystallizes in the orthorhombic P2_12_12_1 space group. Fe(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 56-58°. All Fe(1)-O(1) bond lengths are 1.99 Å. There are a spread of Fe(1)-O(2) bond distances ranging from 2.11-2.15 Å. H(1) is bonded in a single-bond geometry to one O(2) atom. The H(1)-O(2) bond length is 1.00 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to three equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom.