data_IrRu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.36
_cell_length_b   2.74
_cell_length_c   4.76
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   IrRu
_chemical_formula_sum   'Ir2 Ru2'
_cell_volume   56.9
_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
  Ir  Ir0  1  0.27  0.37  0.96  1.0
  Ir  Ir1  1  0.09  0.37  0.8  1.0
  Ru  Ru2  1  0.27  0.0  0.59  1.0
  Ru  Ru3  1  0.09  0.0  0.17  1.0

data_IrRu
_symmetry_space_group_name_H-M   P2
_cell_length_a   4.36
_cell_length_b   2.74
_cell_length_c   4.76
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   3
_chemical_formula_structural   IrRu
_chemical_formula_sum   'Ir2 Ru2'
_cell_volume   56.9
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  Ru  Ru0  2  0.09  0.0  0.21  1.0
  Ir  Ir1  2  0.09  0.37  0.58  1.0

Ir Ir Ru Ru
Ir Ir Ru Ru 0 1 o o o 0 3 o o + 1 2 o o o 