data_[Na18Cd6Hg3]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Cd  1.6900  1.5500  1.0900
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [R-3m]
_cell_length_a [5.5011]
_cell_length_b [5.5011]
_cell_length_c [31.7845]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [166]
_chemical_formula_structural [Na6Cd2Hg]
_chemical_formula_sum '[Na18 Cd6 Hg3]'
_cell_volume [833.0057]
_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  0.1922  1.0
  Na  Na1  6  0.0000  0.0000  0.3027  1.0
  Na  Na2  6  0.0000  0.0000  0.4221  1.0
  Cd  Cd3  6  0.0000  0.0000  0.0918  1.0
  Hg  Hg4  3  0.0000  0.0000  0.0000  1.0
]