data_[Na4Bi2P2Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Bi  2.0200  1.6000  1.0350
  P  2.1900  1.0000  0.5500
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [I-4]
_cell_length_a [6.4488]
_cell_length_b [6.4488]
_cell_length_c [12.8483]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [82]
_chemical_formula_structural [Na2BiPSe4]
_chemical_formula_sum '[Na4 Bi2 P2 Se8]'
_cell_volume [534.3286]
_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  0.0000  0.0000  1
  Na  Na1  2  0.0000  0.5000  0.7500  1
  Bi  Bi2  2  0.0000  0.5000  0.2500  1
  P  P3  2  0.0000  0.0000  0.5000  1
  Se  Se4  8  0.2121  0.7750  0.3866  1
]