data_[Na4Cu4Hg4Cl16]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Cu  1.9000  1.3500  0.8200
  Hg  2.0000  1.5000  1.2450
  Cl  3.1600  1.0000  0.7800
]
_symmetry_space_group_name_H-M [Imma]
_cell_length_a [7.8255]
_cell_length_b [7.9865]
_cell_length_c [10.7738]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [74]
_chemical_formula_structural [NaCuHgCl4]
_chemical_formula_sum '[Na4 Cu4 Hg4 Cl16]'
_cell_volume [673.3530]
_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  4  0.2500  0.2500  0.7500  1
  Cu  Cu1  4  0.0000  0.2500  0.3653  1
  Hg  Hg2  4  0.0000  0.0000  0.0000  1
  Cl  Cl3  8  0.0000  0.0035  0.2449  1
  Cl  Cl4  8  0.2413  0.2500  0.4910  1
]