data_[Na3Bi18Se24]
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
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [9.1667]
_cell_length_b [9.1667]
_cell_length_c [18.4959]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Na(Bi3Se4)2]
_chemical_formula_sum '[Na3 Bi18 Se24]'
_cell_volume [1345.9695]
_cell_formula_units_Z [3]
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  3  0.0000  0.0000  0.0000  1
  Bi  Bi1  18  0.0099  0.7274  0.2527  1
  Se  Se2  18  0.0123  0.7274  0.0927  1
  Se  Se3  6  0.0000  0.0000  0.3184  1
]