data_[Na6Tl18Se18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Tl  1.6200  1.9000  1.3325
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [9.3948]
_cell_length_b [9.3948]
_cell_length_c [17.5815]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Na(TlSe)3]
_chemical_formula_sum '[Na6 Tl18 Se18]'
_cell_volume [1343.8740]
_cell_formula_units_Z [6]
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  6  0.0000  0.0000  0.3228  1
  Tl  Tl1  18  0.0069  0.3095  0.0894  1
  Se  Se2  18  0.0150  0.3068  0.2554  1
]