data_Si2SeCl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.85
_cell_length_b   7.85
_cell_length_c   7.85
_cell_angle_alpha   26.36
_cell_angle_beta   26.36
_cell_angle_gamma   26.36
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2SeCl
_chemical_formula_sum   'Si2 Se1 Cl1'
_cell_volume   84.0
_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
  Si  Si2  1  0.0  0.0  0.54  1.0
  Si  Si3  1  0.0  0.0  0.18  1.0
  Se  Se1  1  0.0  0.0  0.36  1.0
  Cl  Cl0  1  0.0  0.0  0.0  1.0

data_Si2SeCl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.2
_cell_length_b   3.58
_cell_length_c   7.85
_cell_angle_alpha   90.0
_cell_angle_beta   105.26
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Si2SeCl
_chemical_formula_sum   'Si4 Se2 Cl2'
_cell_volume   168.01
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Si  Si0  2  0.0  0.0  0.46  1.0
  Si  Si1  2  0.0  0.0  0.82  1.0
  Se  Se2  2  0.0  0.0  0.64  1.0
  Cl  Cl3  2  0.0  0.0  0.0  1.0

Si Si Se Cl