data_[Na16Sn4Hg4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Sn  1.9600  1.4500  0.8300
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [5.8784]
_cell_length_b [8.0065]
_cell_length_c [15.5525]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [Na4SnHg]
_chemical_formula_sum '[Na16 Sn4 Hg4]'
_cell_volume [731.9813]
_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  8  0.0000  0.2640  0.3553  1.0
  Na  Na1  4  0.0000  0.1775  0.0000  1.0
  Na  Na2  4  0.0000  0.5000  0.1841  1.0
  Sn  Sn3  4  0.0000  0.0000  0.1882  1.0
  Hg  Hg4  4  0.2435  0.0000  0.5000  1.0
]