data_[Na8Se4O4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Se  2.5500  1.1500  1.0133
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P2_1]
_cell_length_a [4.8364]
_cell_length_b [6.3968]
_cell_length_c [10.6126]
_cell_angle_alpha [90.0000]
_cell_angle_beta [101.8655]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [4]
_chemical_formula_structural [Na2SeO]
_chemical_formula_sum '[Na8 Se4 O4]'
_cell_volume [321.3121]
_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
[
  Na  Na0  2  0.0039  0.2713  0.0005  1
  Na  Na1  2  0.2791  0.0111  0.5345  1
  Na  Na2  2  0.4224  0.7743  0.8491  1
  Na  Na3  2  0.4390  0.2632  0.8487  1
  Se  Se4  2  0.1296  0.7107  0.3148  1
  Se  Se5  2  0.1668  0.3295  0.3158  1
  O  O6  2  0.3389  0.5199  0.9923  1
  O  O7  2  0.3459  0.0200  0.0073  1
]