The material described by FeOOH crystallizes in the triclinic P1 space group. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(8) atoms to form a mixture of distorted corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-52°. In the second Fe site, Fe(2) is bonded in a 6-coordinate geometry to one O(2), one O(6), two equivalent O(1), and two equivalent O(7) atoms. In the third Fe site, Fe(3) is bonded to one O(3), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the fourth Fe site, Fe(4) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-52°. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(3) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(4) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(6) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Fe(1), two equivalent Fe(2), and one H(1) atom. In the second O site, O(2) is bonded in a trigonal non-coplanar geometry to one Fe(2) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Fe(3), two equivalent Fe(4), and one H(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Fe(4), two equivalent Fe(3), and one H(3) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Fe(2), two equivalent Fe(4), and one H(4) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.093
_cell_length_b   7.408
_cell_length_c   7.879
_cell_angle_alpha   89.134
_cell_angle_beta   101.156
_cell_angle_gamma   101.650
_symmetry_Int_Tables_number   1
_cell_volume   173.438
_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  0.822  0.472  0.193  1.0
  Fe  Fe1  1  0.159  0.499  0.849  1.0
  Fe  Fe2  1  0.370  0.224  0.527  1.0
  Fe  Fe3  1  0.636  0.817  0.463  1.0
  H  H4  1  0.796  0.763  0.032  1.0
  H  H5  1  0.136  0.020  0.243  1.0
  H  H6  1  0.903  0.053  0.760  1.0
  H  H7  1  0.054  0.572  0.534  1.0
  O  O8  1  0.774  0.657  0.958  1.0
  O  O9  1  0.196  0.355  0.060  1.0
  O  O10  1  0.168  0.981  0.362  1.0
  O  O11  1  0.840  0.053  0.634  1.0
  O  O12  1  0.859  0.326  0.405  1.0
  O  O13  1  0.139  0.695  0.592  1.0
  O  O14  1  0.548  0.389  0.728  1.0
  O  O15  1  0.452  0.640  0.281  1.0
[/CIF]
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The material described by FeOOH crystallizes in the triclinic P1 space group. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(8) atoms to form a mixture of distorted corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-52°. In the second Fe site, Fe(2) is bonded in a 6-coordinate geometry to one O(2), one O(6), two equivalent O(1), and two equivalent O(7) atoms. In the third Fe site, Fe(3) is bonded to one O(3), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the fourth Fe site, Fe(4) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 51-52°. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(3) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(4) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(6) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Fe(1), two equivalent Fe(2), and one H(1) atom. In the second O site, O(2) is bonded in a trigonal non-coplanar geometry to one Fe(2) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Fe(3), two equivalent Fe(4), and one H(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Fe(4), two equivalent Fe(3), and one H(3) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Fe(2), two equivalent Fe(4), and one H(4) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_FeHO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.093
_cell_length_b   7.408
_cell_length_c   7.879
_cell_angle_alpha   89.134
_cell_angle_beta   101.156
_cell_angle_gamma   101.650
_symmetry_Int_Tables_number   1
_cell_volume   173.438
_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  0.822  0.472  0.193  1.0
  Fe  Fe1  1  0.159  0.499  0.849  1.0
  Fe  Fe2  1  0.370  0.224  0.527  1.0
  Fe  Fe3  1  0.636  0.817  0.463  1.0
  H  H4  1  0.796  0.763  0.032  1.0
  H  H5  1  0.136  0.020  0.243  1.0
  H  H6  1  0.903  0.053  0.760  1.0
  H  H7  1  0.054  0.572  0.534  1.0
  O  O8  1  0.774  0.657  0.958  1.0
  O  O9  1  0.196  0.355  0.060  1.0
  O  O10  1  0.168  0.981  0.362  1.0
  O  O11  1  0.840  0.053  0.634  1.0
  O  O12  1  0.859  0.326  0.405  1.0
  O  O13  1  0.139  0.695  0.592  1.0
  O  O14  1  0.548  0.389  0.728  1.0
  O  O15  1  0.452  0.640  0.281  1.0
[/CIF]
.