data_[Na8Hg16Sb8]
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
  Sb  2.0500  1.4500  0.8300
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [4.7319]
_cell_length_b [10.0274]
_cell_length_c [20.3565]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [NaHg2Sb]
_chemical_formula_sum '[Na8 Hg16 Sb8]'
_cell_volume [965.8922]
_cell_formula_units_Z [8]
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  0.0000  0.2747  0.0000  1.0
  Na  Na1  4  0.0000  0.5000  0.1957  1.0
  Hg  Hg2  8  0.0000  0.1427  0.2107  1.0
  Hg  Hg3  4  0.0000  0.0000  0.4306  1.0
  Hg  Hg4  4  0.0000  0.5000  0.4292  1.0
  Sb  Sb5  8  0.0000  0.2460  0.6422  1.0
]