data_[Ac21Si3I36]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ac  1.1000  1.9500  1.2600
  Si  1.9000  1.1000  0.5400
  I  2.6600  1.4000  1.2733
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [16.9081]
_cell_length_b [16.9081]
_cell_length_c [11.2806]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Ac7SiI12]
_chemical_formula_sum '[Ac21 Si3 I36]'
_cell_volume [2792.8906]
_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
[
  Ac  Ac0  18  0.0461  0.1645  0.8461  1
  Ac  Ac1  3  0.0000  0.0000  0.5000  1
  Si  Si2  3  0.0000  0.0000  0.0000  1
  I  I3  18  0.0222  0.5875  0.6658  1
  I  I4  18  0.0518  0.1857  0.3411  1
]