data_IrSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.03
_cell_length_b   5.03
_cell_length_c   4.47
_cell_angle_alpha   96.93
_cell_angle_beta   96.93
_cell_angle_gamma   36.55
_symmetry_Int_Tables_number   1
_chemical_formula_structural   IrSe
_chemical_formula_sum   'Ir2 Se2'
_cell_volume   66.73
_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  0.54  0.0  0.79  1.0
  Ir  Ir1  1  0.43  0.0  0.65  1.0
  Se  Se2  1  0.97  0.0  0.33  1.0
  Se  Se3  1  0.0  0.0  0.1  1.0

data_IrSe
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.15
_cell_length_b   4.47
_cell_length_c   5.03
_cell_angle_alpha   96.93
_cell_angle_beta   108.28
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   IrSe
_chemical_formula_sum   'Ir2 Se2'
_cell_volume   66.73
_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  0.0  0.43  0.94  1.0
  Se  Se1  2  0.0  0.11  0.48  1.0

Ir Ir Se Se
Ir Ir Se Se 0 1 o o o 2 3 + o o 