data_PbSeCl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.24
_cell_length_b   7.24
_cell_length_c   4.33
_cell_angle_alpha   106.11
_cell_angle_beta   106.11
_cell_angle_gamma   30.92
_symmetry_Int_Tables_number   1
_chemical_formula_structural   PbSeCl2
_chemical_formula_sum   'Pb1 Se1 Cl2'
_cell_volume   111.6
_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
  Pb  Pb2  1  0.65  0.0  0.81  1.0
  Se  Se3  1  0.39  0.0  0.13  1.0
  Cl  Cl0  1  0.24  0.0  0.07  1.0
  Cl  Cl1  1  0.8  0.0  0.21  1.0

data_PbSeCl2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.86
_cell_length_b   4.33
_cell_length_c   7.24
_cell_angle_alpha   106.11
_cell_angle_beta   105.46
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   PbSeCl2
_chemical_formula_sum   'Pb1 Se1 Cl2'
_cell_volume   111.6
_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
  Pb  Pb0  1  0.0  0.81  0.65  1.0
  Se  Se1  1  0.0  0.13  0.39  1.0
  Cl  Cl2  1  0.0  0.07  0.24  1.0
  Cl  Cl3  1  0.0  0.21  0.8  1.0

Pb Se Cl Cl
Pb Se Cl Cl 0 3 o o + 1 2 o o o 