The structure described by FeO2 is Hydrophilite-like structured and crystallizes in the monoclinic P2/m space group. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), two equivalent O(7), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. In the third Fe site, Fe(3) is bonded to one O(5), one O(8), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. In the fourth Fe site, Fe(4) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Fe(2) and two equivalent Fe(4) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1) and two equivalent Fe(4) atoms. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Fe(3) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Fe(4) and two equivalent Fe(2) atoms. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms. is represented by the CIF card [CIF]
data_FeO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.942
_cell_length_b   7.385
_cell_length_c   7.421
_cell_angle_alpha   86.712
_cell_angle_beta   78.568
_cell_angle_gamma   78.512
_symmetry_Int_Tables_number   1
_cell_volume   154.829
_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  0.352  0.816  0.480  1.0
  Fe  Fe1  1  0.834  0.515  0.817  1.0
  Fe  Fe2  1  0.648  0.184  0.520  1.0
  Fe  Fe3  1  0.166  0.485  0.183  1.0
  O  O4  1  0.154  0.056  0.636  1.0
  O  O5  1  0.158  0.297  0.387  1.0
  O  O6  1  0.786  0.365  0.063  1.0
  O  O7  1  0.545  0.621  0.289  1.0
  O  O8  1  0.846  0.944  0.364  1.0
  O  O9  1  0.842  0.703  0.613  1.0
  O  O10  1  0.214  0.635  0.937  1.0
  O  O11  1  0.455  0.379  0.711  1.0
[/CIF]
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The structure described by FeO2 is Hydrophilite-like structured and crystallizes in the monoclinic P2/m space group. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), two equivalent O(7), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. In the third Fe site, Fe(3) is bonded to one O(5), one O(8), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. In the fourth Fe site, Fe(4) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Fe(2) and two equivalent Fe(4) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1) and two equivalent Fe(4) atoms. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Fe(3) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Fe(4) and two equivalent Fe(2) atoms. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms. is represented by the CIF card [CIF]
data_FeO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.942
_cell_length_b   7.385
_cell_length_c   7.421
_cell_angle_alpha   86.712
_cell_angle_beta   78.568
_cell_angle_gamma   78.512
_symmetry_Int_Tables_number   1
_cell_volume   154.829
_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  0.352  0.816  0.480  1.0
  Fe  Fe1  1  0.834  0.515  0.817  1.0
  Fe  Fe2  1  0.648  0.184  0.520  1.0
  Fe  Fe3  1  0.166  0.485  0.183  1.0
  O  O4  1  0.154  0.056  0.636  1.0
  O  O5  1  0.158  0.297  0.387  1.0
  O  O6  1  0.786  0.365  0.063  1.0
  O  O7  1  0.545  0.621  0.289  1.0
  O  O8  1  0.846  0.944  0.364  1.0
  O  O9  1  0.842  0.703  0.613  1.0
  O  O10  1  0.214  0.635  0.937  1.0
  O  O11  1  0.455  0.379  0.711  1.0
[/CIF]
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