data_[Na6Hg3O3]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [R3m]
_cell_length_a [3.6750]
_cell_length_b [3.6750]
_cell_length_c [22.1437]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [160]
_chemical_formula_structural [Na2HgO]
_chemical_formula_sum '[Na6 Hg3 O3]'
_cell_volume [258.9953]
_cell_formula_units_Z [3]
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  3  0.0000  0.0000  0.7090  1.0
  Na  Na1  3  0.0000  0.0000  0.9584  1.0
  Hg  Hg2  3  0.0000  0.0000  0.4978  1.0
  O  O3  3  0.0000  0.0000  0.3348  1.0
]