data_[Na2Hg2Br8]
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
  Br  2.9600  1.1500  0.8825
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [14.9366]
_cell_length_b [4.2423]
_cell_length_c [18.7463]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [NaHgBr4]
_chemical_formula_sum '[Na2 Hg2 Br8]'
_cell_volume [1187.8816]
_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
[
  Na  Na0  2  0.1515  0.7500  0.4967  1
  Hg  Hg1  2  0.3760  0.2500  0.5169  1
  Br  Br2  2  0.0336  0.2500  0.5646  1
  Br  Br3  2  0.2519  0.2500  0.4194  1
  Br  Br4  2  0.2987  0.7500  0.5999  1
  Br  Br5  2  0.4731  0.7500  0.4149  1
]