data_[Na18Tl36Hg3]
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
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [11.9235]
_cell_length_b [11.9235]
_cell_length_c [13.9031]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Na6Tl12Hg]
_chemical_formula_sum '[Na18 Tl36 Hg3]'
_cell_volume [1711.7796]
_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  18  0.0291  0.5940  0.7098  1.0
  Tl  Tl1  18  0.0387  0.8539  0.8119  1.0
  Tl  Tl2  18  0.0610  0.2038  0.4087  1.0
  Hg  Hg3  3  0.0000  0.0000  0.0000  1.0
]