data_IrAu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.8
_cell_length_b   3.77
_cell_length_c   6.3
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   IrAu
_chemical_formula_sum   'Ir2 Au2'
_cell_volume   66.6
_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  Ir2  1  0.0  0.0  0.57  1.0
  Ir  Ir3  1  0.4  0.88  0.73  1.0
  Au  Au0  1  0.0  0.0  0.98  1.0
  Au  Au1  1  0.4  0.88  0.32  1.0

data_IrAu
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.8
_cell_length_b   3.77
_cell_length_c   6.3
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   IrAu
_chemical_formula_sum   'Ir2 Au2'
_cell_volume   66.6
_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
  Ir  Ir0  2  0.2  0.44  0.58  1.0
  Au  Au1  2  0.2  0.44  0.17  1.0

Ir Ir Au Au
Ir Ir Au Au 0 1 o - o 0 2 o o o 0 3 o - o 0 3 - - o 1 2 + + o 1 2 o + o 1 3 o o o 2 3 o - + 