data_[K2Na16Hg4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  Na  0.9300  1.8000  1.1600
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [16.7399]
_cell_length_b [5.5747]
_cell_length_c [9.1618]
_cell_angle_alpha [90.0000]
_cell_angle_beta [116.1085]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [K(Na4Hg)2]
_chemical_formula_sum '[K2 Na16 Hg4]'
_cell_volume [767.7327]
_cell_formula_units_Z [2]
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
[
  K  K0  2  0.0000  0.5000  0.0000  1
  Na  Na1  4  0.0643  0.0000  0.7187  1
  Na  Na2  4  0.1082  0.5000  0.4853  1
  Na  Na3  4  0.1650  0.0000  0.3277  1
  Na  Na4  4  0.2161  0.5000  0.8972  1
  Hg  Hg5  4  0.2462  0.5000  0.2774  1
]