data_C3I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.29
_cell_length_b   5.29
_cell_length_c   5.29
_cell_angle_alpha   135.83
_cell_angle_beta   98.14
_cell_angle_gamma   98.11
_symmetry_Int_Tables_number   1
_chemical_formula_structural   C3I
_chemical_formula_sum   'C3 I1'
_cell_volume   95.69
_cell_formula_units_Z   1
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
  C  C0  1  0.0  0.29  0.0  1.0
  C  C1  1  0.0  0.64  0.0  1.0
  C  C2  1  0.0  0.0  0.0  1.0
  I  I3  1  0.0  0.47  0.0  1.0

data_C3I
_symmetry_space_group_name_H-M   Cm
_cell_length_a   3.98
_cell_length_b   9.81
_cell_length_c   5.29
_cell_angle_alpha   90.0
_cell_angle_beta   112.08
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   C3I
_chemical_formula_sum   'C6 I2'
_cell_volume   191.38
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  C  C0  2  0.0  0.0  0.0  1.0
  C  C1  2  0.0  0.0  0.36  1.0
  C  C2  2  0.0  0.0  0.71  1.0
  I  I3  2  0.0  0.0  0.53  1.0

C C C I