data_Cr2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.47
_cell_length_b   4.47
_cell_length_c   6.95
_cell_angle_alpha   107.95
_cell_angle_beta   107.95
_cell_angle_gamma   39.52
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cr2Se
_chemical_formula_sum   'Cr4 Se2'
_cell_volume   83.39
_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
  Cr  Cr0  1  0.98  0.0  0.55  1.0
  Cr  Cr1  1  0.64  0.0  0.62  1.0
  Cr  Cr2  1  0.49  0.0  0.95  1.0
  Cr  Cr3  1  0.15  0.0  0.02  1.0
  Se  Se4  1  0.89  0.0  0.43  1.0
  Se  Se5  1  0.24  0.0  0.14  1.0

data_Cr2Se
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.02
_cell_length_b   4.47
_cell_length_c   6.95
_cell_angle_alpha   107.95
_cell_angle_beta   90.0
_cell_angle_gamma   109.76
_symmetry_Int_Tables_number   2
_chemical_formula_structural   Cr2Se
_chemical_formula_sum   'Cr4 Se2'
_cell_volume   83.39
_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
  Cr  Cr0  2  0.0  0.08  0.83  1.0
  Cr  Cr1  2  0.0  0.41  0.77  1.0
  Se  Se2  2  0.0  0.33  0.65  1.0

Cr Cr Cr Cr Se Se
Cr Cr Cr Cr Se Se 0 4 o o o 0 1 o o o 1 4 o o o 2 5 o o + 2 3 o o + 3 5 o o o 