data_C2I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.37
_cell_length_b   4.37
_cell_length_c   7.0
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   87.68
_symmetry_Int_Tables_number   1
_chemical_formula_structural   C2I
_chemical_formula_sum   'C4 I2'
_cell_volume   133.34
_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
  C  C0  1  0.8  0.05  0.75  1.0
  C  C1  1  0.5  0.95  0.25  1.0
  C  C2  1  0.5  0.05  0.75  1.0
  C  C3  1  0.8  0.95  0.25  1.0
  I  I4  1  0.15  0.16  0.75  1.0
  I  I5  1  0.15  0.84  0.25  1.0

data_C2I
_symmetry_space_group_name_H-M   Pmma
_cell_length_a   7.0
_cell_length_b   4.37
_cell_length_c   4.37
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   51
_chemical_formula_structural   C2I
_chemical_formula_sum   'C4 I2'
_cell_volume   133.45
_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, z'
  4  'x+1/2, y, -z'
  5  'x+1/2, -y, -z'
  6  '-x+1/2, y, z'
  7  '-x, y, -z'
  8  '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  4  0.25  0.35  0.95  1.0
  I  I1  2  0.25  0.0  0.84  1.0

C C C C I I
C C C C I I 0 2 o o o 0 4 + o o 1 5 o o o 1 3 o o o 2 4 o o o 3 5 + o o 