The crystal structure described by FeOOH crystallizes in the monoclinic P2_1 space group. Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 22°. H(1) is bonded in a distorted linear geometry to two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Fe(1) atoms to form a mixture of edge and corner-sharing OFe4 trigonal pyramids. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Fe(1) and two equivalent H(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.054
_cell_length_b   3.932
_cell_length_c   6.338
_cell_angle_alpha   90.001
_cell_angle_beta   103.936
_cell_angle_gamma   90.009
_symmetry_Int_Tables_number   1
_cell_volume   73.864
_cell_formula_units_Z   2
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  0.677  0.753  0.355  1.0
  Fe  Fe1  1  0.323  0.253  0.645  1.0
  H  H2  1  0.017  0.559  0.034  1.0
  H  H3  1  0.983  0.059  0.966  1.0
  O  O4  1  0.292  0.750  0.584  1.0
  O  O5  1  0.708  0.250  0.416  1.0
  O  O6  1  0.070  0.752  0.141  1.0
  O  O7  1  0.930  0.252  0.859  1.0
[/CIF]
.
The crystal structure described by FeOOH crystallizes in the monoclinic P2_1 space group. Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 22°. H(1) is bonded in a distorted linear geometry to two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Fe(1) atoms to form a mixture of edge and corner-sharing OFe4 trigonal pyramids. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Fe(1) and two equivalent H(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.054
_cell_length_b   3.932
_cell_length_c   6.338
_cell_angle_alpha   90.001
_cell_angle_beta   103.936
_cell_angle_gamma   90.009
_symmetry_Int_Tables_number   1
_cell_volume   73.864
_cell_formula_units_Z   2
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  0.677  0.753  0.355  1.0
  Fe  Fe1  1  0.323  0.253  0.645  1.0
  H  H2  1  0.017  0.559  0.034  1.0
  H  H3  1  0.983  0.059  0.966  1.0
  O  O4  1  0.292  0.750  0.584  1.0
  O  O5  1  0.708  0.250  0.416  1.0
  O  O6  1  0.070  0.752  0.141  1.0
  O  O7  1  0.930  0.252  0.859  1.0
[/CIF]
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