data_[Na6Mg4Hg8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Mg  1.3100  1.5000  0.8600
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [11.3136]
_cell_length_b [5.0825]
_cell_length_c [9.4693]
_cell_angle_alpha [90.0000]
_cell_angle_beta [125.1131]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na3(MgHg2)2]
_chemical_formula_sum '[Na6 Mg4 Hg8]'
_cell_volume [445.4077]
_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  4  0.1588  0.5000  0.6775  1.0
  Na  Na1  2  0.0000  0.0000  0.0000  1.0
  Mg  Mg2  4  0.1264  0.5000  0.2966  1.0
  Hg  Hg3  4  0.0603  0.0000  0.3875  1.0
  Hg  Hg4  4  0.2075  0.5000  0.0523  1.0
]