data_[Na6Fe2O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Fe  1.8300  1.4000  0.8525
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P2/c]
_cell_length_a [5.7470]
_cell_length_b [6.4851]
_cell_length_c [5.3253]
_cell_angle_alpha [90.0000]
_cell_angle_beta [110.1396]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [13]
_chemical_formula_structural [Na3FeO4]
_chemical_formula_sum '[Na6 Fe2 O8]'
_cell_volume [186.3351]
_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
[
  Na  Na0  2  0.0000  0.1186  0.2500  1.0
  Na  Na1  2  0.0000  0.3740  0.7500  1.0
  Na  Na2  2  0.5000  0.3814  0.2500  1.0
  Fe  Fe3  2  0.5000  0.1264  0.7500  1.0
  O  O4  4  0.2813  0.3230  0.5510  1.0
  O  O5  4  0.3127  0.0960  0.9914  1.0
]