The material structure described by Na2FeO2 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to two equivalent O(2) and three equivalent O(1) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 tetrahedra. Fe(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to two equivalent Na(2), three equivalent Na(1), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Fe(1) atoms to form a mixture of edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles are 57°. is represented by the CIF file [CIF]
data_Na2FeO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.007
_cell_length_b   5.506
_cell_length_c   8.506
_cell_angle_alpha   90.001
_cell_angle_beta   90.000
_cell_angle_gamma   74.154
_symmetry_Int_Tables_number   1
_cell_volume   135.448
_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  0.123  0.755  0.004  1.0
  Fe  Fe1  1  0.877  0.245  0.504  1.0
  Na  Na2  1  0.144  0.713  0.667  1.0
  Na  Na3  1  0.856  0.287  0.167  1.0
  Na  Na4  1  0.391  0.218  0.847  1.0
  Na  Na5  1  0.609  0.782  0.347  1.0
  O  O6  1  0.273  0.454  0.404  1.0
  O  O7  1  0.727  0.545  0.904  1.0
  O  O8  1  0.485  0.030  0.593  1.0
  O  O9  1  0.515  0.970  0.093  1.0
[/CIF]
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The material structure described by Na2FeO2 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to two equivalent O(2) and three equivalent O(1) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 tetrahedra. Fe(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to two equivalent Na(2), three equivalent Na(1), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Fe(1) atoms to form a mixture of edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles are 57°. is represented by the CIF file [CIF]
data_Na2FeO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.007
_cell_length_b   5.506
_cell_length_c   8.506
_cell_angle_alpha   90.001
_cell_angle_beta   90.000
_cell_angle_gamma   74.154
_symmetry_Int_Tables_number   1
_cell_volume   135.448
_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  0.123  0.755  0.004  1.0
  Fe  Fe1  1  0.877  0.245  0.504  1.0
  Na  Na2  1  0.144  0.713  0.667  1.0
  Na  Na3  1  0.856  0.287  0.167  1.0
  Na  Na4  1  0.391  0.218  0.847  1.0
  Na  Na5  1  0.609  0.782  0.347  1.0
  O  O6  1  0.273  0.454  0.404  1.0
  O  O7  1  0.727  0.545  0.904  1.0
  O  O8  1  0.485  0.030  0.593  1.0
  O  O9  1  0.515  0.970  0.093  1.0
[/CIF]
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