data_[Na20Hg8Pb8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Hg  2.0000  1.5000  1.2450
  Pb  2.3300  1.8000  1.1225
]
_symmetry_space_group_name_H-M [Cmce]
_cell_length_a [17.8661]
_cell_length_b [7.8562]
_cell_length_c [7.7617]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [64]
_chemical_formula_structural [Na5(HgPb)2]
_chemical_formula_sum '[Na20 Hg8 Pb8]'
_cell_volume [1089.4336]
_cell_formula_units_Z [4]
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  16  0.1396  0.2146  0.7140  1.0
  Na  Na1  4  0.0000  0.0000  0.0000  1.0
  Hg  Hg2  8  0.0000  0.1299  0.3748  1.0
  Pb  Pb3  8  0.2426  0.0000  0.0000  1.0
]