data_[Na2Sn2Bi2Se6]
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 [P2_1/m]
_cell_length_a [8.6335]
_cell_length_b [4.1827]
_cell_length_c [10.0818]
_cell_angle_alpha [90.0000]
_cell_angle_beta [95.6277]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [NaSnBiSe3]
_chemical_formula_sum '[Na2 Sn2 Bi2 Se6]'
_cell_volume [362.3189]
_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  0.1328  0.2500  0.1438  1.0
  Sn  Sn1  2  0.1460  0.2500  0.5491  1.0
  Bi  Bi2  2  0.3759  0.7500  0.8443  1.0
  Se  Se3  2  0.1170  0.2500  0.8226  1.0
  Se  Se4  2  0.3541  0.7500  0.5556  1.0
  Se  Se5  2  0.3867  0.7500  0.1430  1.0
]