data_[Na21Tl15]
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
]
_symmetry_space_group_name_H-M [R-3m]
_cell_length_a [5.3932]
_cell_length_b [5.3932]
_cell_length_c [43.4082]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [166]
_chemical_formula_structural [Na7Tl5]
_chemical_formula_sum '[Na21 Tl15]'
_cell_volume [1093.4390]
_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  6  0.0000  0.0000  0.0743  1
  Na  Na1  6  0.0000  0.0000  0.2235  1
  Na  Na2  6  0.0000  0.0000  0.3081  1
  Na  Na3  3  -0.0000  -0.0000  0.5000  1
  Tl  Tl4  6  0.0000  0.0000  0.1482  1
  Tl  Tl5  6  0.0000  0.0000  0.3872  1
  Tl  Tl6  3  0.0000  0.0000  0.0000  1
]