data_[Nd21Si3I36]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Nd  1.1400  1.8500  1.2765
  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 [16.1256]
_cell_length_b [16.1256]
_cell_length_c [10.7916]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Nd7SiI12]
_chemical_formula_sum '[Nd21 Si3 I36]'
_cell_volume [2430.2339]
_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
[
  Nd  Nd0  18  0.0460  0.1629  0.8509  1
  Nd  Nd1  3  0.0000  0.0000  0.5000  1
  Si  Si2  3  0.0000  0.0000  0.0000  1
  I  I3  18  0.0217  0.5870  0.6655  1
  I  I4  18  0.0515  0.1832  0.3377  1
]