data_[Na6Hg6F18]
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
  F  3.9800  0.5000  0.7050
]
_symmetry_space_group_name_H-M [R3c]
_cell_length_a [5.9548]
_cell_length_b [5.9548]
_cell_length_c [15.4678]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [161]
_chemical_formula_structural [NaHgF3]
_chemical_formula_sum '[Na6 Hg6 F18]'
_cell_volume [474.9922]
_cell_formula_units_Z [6]
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  0.2929  1.0
  Hg  Hg1  6  0.0000  0.0000  0.0067  1.0
  F  F2  18  0.0011  0.7049  0.8988  1.0
]