data_[Na8Sn4Bi4Se20]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Sn  1.9600  1.4500  0.8300
  Bi  2.0200  1.6000  1.0350
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Cmc2_1]
_cell_length_a [3.9727]
_cell_length_b [19.3510]
_cell_length_c [13.5426]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [36]
_chemical_formula_structural [Na2SnBiSe5]
_chemical_formula_sum '[Na8 Sn4 Bi4 Se20]'
_cell_volume [1041.0983]
_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  4  0.0000  0.0988  0.6529  1.0
  Na  Na1  4  0.0000  0.1198  0.3217  1.0
  Sn  Sn2  4  0.0000  0.4330  0.4213  1.0
  Bi  Bi3  4  0.0000  0.2312  0.0476  1.0
  Se  Se4  4  0.0000  0.0472  0.0443  1.0
  Se  Se5  4  0.0000  0.2608  0.6967  1.0
  Se  Se6  4  0.0000  0.3024  0.3833  1.0
  Se  Se7  4  0.0000  0.3643  0.9928  1.0
  Se  Se8  4  0.0000  0.4994  0.2632  1.0
]