data_[Cs6Ca3Hg3I18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Cs  0.7900  2.6000  1.8100
  Ca  1.0000  1.8000  1.1400
  Hg  2.0000  1.5000  1.2450
  I  2.6600  1.4000  1.2733
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [8.7963]
_cell_length_b [8.7963]
_cell_length_c [20.8033]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Cs2CaHgI6]
_chemical_formula_sum '[Cs6 Ca3 Hg3 I18]'
_cell_volume [1393.9960]
_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
[
  Cs  Cs0  6  0.0000  0.0000  0.2520  1.0
  Ca  Ca1  3  -0.0000  0.0000  0.0000  1.0
  Hg  Hg2  3  -0.0000  0.0000  0.5000  1.0
  I  I3  18  0.0054  0.4464  0.2497  1.0
]