data_CrCu2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.72
_cell_length_b   3.72
_cell_length_c   4.19
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.99
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CrCu2Se
_chemical_formula_sum   'Cr1 Cu2 Se1'
_cell_volume   57.91
_cell_formula_units_Z   1
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
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.3  0.33  0.1  1.0
  Cu  Cu2  1  0.3  0.67  0.1  1.0
  Se  Se3  1  0.61  0.0  0.0  1.0

data_CrCu2Se
_symmetry_space_group_name_H-M   Pm
_cell_length_a   3.72
_cell_length_b   3.72
_cell_length_c   4.19
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   CrCu2Se
_chemical_formula_sum   'Cr1 Cu2 Se1'
_cell_volume   57.92
_cell_formula_units_Z   1
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
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  2  0.3  0.33  0.1  1.0
  Se  Se2  1  0.61  0.0  0.0  1.0

Cr Cu Cu Se
Cr Cu Cu Se 0 3 - o o 0 2 o - o 0 1 o o o 1 2 o o o 1 3 o o o 2 3 o + o 