data_[Rb12Na4Hg4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Na  0.9300  1.8000  1.1600
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [21.0445]
_cell_length_b [5.0874]
_cell_length_c [11.2877]
_cell_angle_alpha [90.0000]
_cell_angle_beta [93.0887]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Rb3NaHg]
_chemical_formula_sum '[Rb12 Na4 Hg4]'
_cell_volume [1206.7122]
_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
[
  Rb  Rb0  4  0.0619  0.0000  0.2180  1
  Rb  Rb1  4  0.1053  0.5000  0.5629  1
  Rb  Rb2  4  0.2463  0.0000  0.8029  1
  Na  Na3  4  0.0866  0.5000  0.9294  1
  Hg  Hg4  4  0.2173  0.0000  0.4444  1
]