data_[Si2I8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Si  1.9000  1.1000  0.5400
  I  2.6600  1.4000  1.2733
]
_symmetry_space_group_name_H-M [P1]
_cell_length_a [7.3093]
_cell_length_b [12.4516]
_cell_length_c [20.2151]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.4104]
_symmetry_Int_Tables_number [1]
_chemical_formula_structural [SiI4]
_chemical_formula_sum '[Si2 I8]'
_cell_volume [1839.7662]
_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
[
  Si  Si0  1  0.1031  0.9743  0.4816  1
  Si  Si1  1  0.5967  0.5256  0.5184  1
  I  I2  1  0.0736  0.8931  0.3714  1
  I  I3  1  0.4285  0.9989  0.5094  1
  I  I4  1  0.4467  0.3479  0.5167  1
  I  I5  1  0.4481  0.6432  0.4373  1
  I  I6  1  0.5714  0.6043  0.6294  1
  I  I7  1  0.9209  0.5040  0.4890  1
  I  I8  1  0.9544  0.1512  0.4824  1
  I  I9  1  0.9567  0.8575  0.5643  1
]