data_[Na8Ir2O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ir  2.2000  1.3500  0.7650
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [I4/m]
_cell_length_a [7.2526]
_cell_length_b [7.2526]
_cell_length_c [4.7642]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [87]
_chemical_formula_structural [Na4IrO4]
_chemical_formula_sum '[Na8 Ir2 O8]'
_cell_volume [250.6002]
_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  8  0.0951  0.3027  0.5000  1.0
  Ir  Ir1  2  0.0000  0.0000  0.0000  1.0
  O  O2  8  0.0825  0.2543  0.0000  1.0
]