data_[Na12Sn20Bi8]
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
]
_symmetry_space_group_name_H-M [Ibam]
_cell_length_a [13.6095]
_cell_length_b [14.3505]
_cell_length_c [6.8919]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [72]
_chemical_formula_structural [Na3Sn5Bi2]
_chemical_formula_sum '[Na12 Sn20 Bi8]'
_cell_volume [1346.0007]
_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  8  0.1250  0.2463  0.0000  1.0
  Na  Na1  4  0.0000  0.0000  0.2500  1.0
  Sn  Sn2  8  0.1237  0.3706  0.5000  1.0
  Sn  Sn3  8  0.2473  0.0000  0.2500  1.0
  Sn  Sn4  4  0.0000  0.5000  0.2500  1.0
  Bi  Bi5  8  0.1384  0.1560  0.5000  1.0
]