The material described by FeOOH crystallizes in the orthorhombic Pnma 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 are 56°. H(1) is bonded in a single-bond geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom. In the second O site, O(2) is bonded to three equivalent Fe(1) and one H(1) atom to form distorted corner-sharing OFe3H tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.031
_cell_length_b   4.604
_cell_length_c   9.967
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   139.067
_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  0.750  0.557  0.643  1.0
  Fe  Fe1  1  0.250  0.443  0.357  1.0
  Fe  Fe2  1  0.750  0.943  0.143  1.0
  Fe  Fe3  1  0.250  0.057  0.857  1.0
  H  H4  1  0.750  0.599  0.910  1.0
  H  H5  1  0.250  0.099  0.590  1.0
  H  H6  1  0.250  0.401  0.090  1.0
  H  H7  1  0.750  0.901  0.410  1.0
  O  O8  1  0.750  0.802  0.944  1.0
  O  O9  1  0.250  0.693  0.195  1.0
  O  O10  1  0.750  0.193  0.305  1.0
  O  O11  1  0.250  0.807  0.695  1.0
  O  O12  1  0.250  0.198  0.056  1.0
  O  O13  1  0.750  0.698  0.444  1.0
  O  O14  1  0.250  0.302  0.556  1.0
  O  O15  1  0.750  0.307  0.805  1.0
[/CIF]
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The material described by FeOOH crystallizes in the orthorhombic Pnma 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 are 56°. H(1) is bonded in a single-bond geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom. In the second O site, O(2) is bonded to three equivalent Fe(1) and one H(1) atom to form distorted corner-sharing OFe3H tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.031
_cell_length_b   4.604
_cell_length_c   9.967
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   139.067
_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  0.750  0.557  0.643  1.0
  Fe  Fe1  1  0.250  0.443  0.357  1.0
  Fe  Fe2  1  0.750  0.943  0.143  1.0
  Fe  Fe3  1  0.250  0.057  0.857  1.0
  H  H4  1  0.750  0.599  0.910  1.0
  H  H5  1  0.250  0.099  0.590  1.0
  H  H6  1  0.250  0.401  0.090  1.0
  H  H7  1  0.750  0.901  0.410  1.0
  O  O8  1  0.750  0.802  0.944  1.0
  O  O9  1  0.250  0.693  0.195  1.0
  O  O10  1  0.750  0.193  0.305  1.0
  O  O11  1  0.250  0.807  0.695  1.0
  O  O12  1  0.250  0.198  0.056  1.0
  O  O13  1  0.750  0.698  0.444  1.0
  O  O14  1  0.250  0.302  0.556  1.0
  O  O15  1  0.750  0.307  0.805  1.0
[/CIF]
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