The crystal structure described by FeOOH crystallizes in the tetragonal I-4 space group. Fe(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 52-54°. H(1) is bonded in a single-bond geometry to one O(1) atom. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to three equivalent Fe(1) atoms. In the second O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom. is represented by the CIF file [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.253
_cell_length_b   7.253
_cell_length_c   7.253
_cell_angle_alpha   92.458
_cell_angle_beta   92.458
_cell_angle_gamma   156.095
_symmetry_Int_Tables_number   1
_cell_volume   151.242
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Fe  Fe0  1  0.855  0.655  0.485  1.0
  Fe  Fe1  1  0.171  0.370  0.515  1.0
  Fe  Fe2  1  0.345  0.829  0.199  1.0
  Fe  Fe3  1  0.630  0.145  0.801  1.0
  H  H4  1  0.001  0.022  0.767  1.0
  H  H5  1  0.255  0.234  0.233  1.0
  H  H6  1  0.978  0.745  0.980  1.0
  H  H7  1  0.766  0.999  0.020  1.0
  O  O8  1  0.829  0.874  0.639  1.0
  O  O9  1  0.235  0.190  0.361  1.0
  O  O10  1  0.126  0.765  0.955  1.0
  O  O11  1  0.810  0.171  0.045  1.0
  O  O12  1  0.827  0.452  0.292  1.0
  O  O13  1  0.160  0.536  0.708  1.0
  O  O14  1  0.548  0.840  0.376  1.0
  O  O15  1  0.464  0.173  0.624  1.0
[/CIF]
.
The crystal structure described by FeOOH crystallizes in the tetragonal I-4 space group. Fe(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 52-54°. H(1) is bonded in a single-bond geometry to one O(1) atom. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to three equivalent Fe(1) atoms. In the second O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom. is represented by the CIF file [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.253
_cell_length_b   7.253
_cell_length_c   7.253
_cell_angle_alpha   92.458
_cell_angle_beta   92.458
_cell_angle_gamma   156.095
_symmetry_Int_Tables_number   1
_cell_volume   151.242
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Fe  Fe0  1  0.855  0.655  0.485  1.0
  Fe  Fe1  1  0.171  0.370  0.515  1.0
  Fe  Fe2  1  0.345  0.829  0.199  1.0
  Fe  Fe3  1  0.630  0.145  0.801  1.0
  H  H4  1  0.001  0.022  0.767  1.0
  H  H5  1  0.255  0.234  0.233  1.0
  H  H6  1  0.978  0.745  0.980  1.0
  H  H7  1  0.766  0.999  0.020  1.0
  O  O8  1  0.829  0.874  0.639  1.0
  O  O9  1  0.235  0.190  0.361  1.0
  O  O10  1  0.126  0.765  0.955  1.0
  O  O11  1  0.810  0.171  0.045  1.0
  O  O12  1  0.827  0.452  0.292  1.0
  O  O13  1  0.160  0.536  0.708  1.0
  O  O14  1  0.548  0.840  0.376  1.0
  O  O15  1  0.464  0.173  0.624  1.0
[/CIF]
.