data_SiIr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.97
_cell_length_b   7.97
_cell_length_c   7.97
_cell_angle_alpha   20.96
_cell_angle_beta   20.96
_cell_angle_gamma   20.96
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiIr
_chemical_formula_sum   'Si2 Ir2'
_cell_volume   56.76
_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  Si2  1  0.0  0.0  0.76  1.0
  Si  Si3  1  0.0  0.0  0.63  1.0
  Ir  Ir0  1  0.0  0.0  0.68  1.0
  Ir  Ir1  1  0.0  0.0  0.7  1.0

data_SiIr
_symmetry_space_group_name_H-M   C2/m
_cell_length_a   5.02
_cell_length_b   2.9
_cell_length_c   7.97
_cell_angle_alpha   90.0
_cell_angle_beta   102.12
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   12
_chemical_formula_structural   SiIr
_chemical_formula_sum   'Si4 Ir4'
_cell_volume   113.53
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-x, -y, -z'
  3  '-x, y, -z'
  4  'x, -y, z'
  5  'x+1/2, y+1/2, z'
  6  '-x+1/2, -y+1/2, -z'
  7  '-x+1/2, y+1/2, -z'
  8  '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
  Si  Si0  4  0.0  0.0  0.06  1.0
  Ir  Ir1  4  0.0  0.0  0.01  1.0

Si Si Ir Ir