data_[Na8Hg20Pb8]
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 [Imma]
_cell_length_a [10.6578]
_cell_length_b [16.5148]
_cell_length_c [5.6560]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [74]
_chemical_formula_structural [Na2Hg5Pb2]
_chemical_formula_sum '[Na8 Hg20 Pb8]'
_cell_volume [995.5184]
_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  8  0.2500  0.1425  0.7500  1
  Hg  Hg1  8  0.0000  0.1340  0.0326  1
  Hg  Hg2  8  0.2500  0.0547  0.2500  1
  Hg  Hg3  4  0.0000  0.2500  0.5705  1
  Pb  Pb4  4  0.0000  0.0000  0.5000  1
  Pb  Pb5  4  0.2500  0.2500  0.2500  1
]