data_[Na8Tl16Hg8]
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 [Cmce]
_cell_length_a [6.7718]
_cell_length_b [16.0928]
_cell_length_c [8.7984]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [64]
_chemical_formula_structural [NaTl2Hg]
_chemical_formula_sum '[Na8 Tl16 Hg8]'
_cell_volume [958.8199]
_cell_formula_units_Z [8]
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  0.0000  0.1223  0.4522  1
  Tl  Tl1  8  0.0000  0.1487  0.0649  1
  Tl  Tl2  8  0.2500  0.2085  0.7500  1
  Hg  Hg3  8  0.0000  0.0245  0.7746  1
]