data_[Na4H8Se2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  H  2.2000  0.2500  0.0000
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Pbam]
_cell_length_a [6.2220]
_cell_length_b [11.9958]
_cell_length_c [3.0528]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [55]
_chemical_formula_structural [Na2H4Se]
_chemical_formula_sum '[Na4 H8 Se2]'
_cell_volume [227.8544]
_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  4  0.2442  0.2540  0.5000  1
  H  H1  4  0.0077  0.7125  0.0000  1
  H  H2  4  0.1558  0.0056  0.0000  1
  Se  Se3  2  0.0000  0.0000  0.5000  1
]