data_[Rb8Hg4Se2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Hg  2.0000  1.5000  1.2450
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [I4/mmm]
_cell_length_a [6.7769]
_cell_length_b [6.7769]
_cell_length_c [17.5050]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [139]
_chemical_formula_structural [Rb4Hg2Se]
_chemical_formula_sum '[Rb8 Hg4 Se2]'
_cell_volume [803.9479]
_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
[
  Rb  Rb0  4  0.0000  0.0000  0.1866  1
  Rb  Rb1  4  0.0000  0.5000  0.0000  1
  Hg  Hg2  4  0.0000  0.0000  0.4054  1
  Se  Se3  2  0.0000  0.0000  0.0000  1
]