data_Si(SbSe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.9
_cell_length_b   5.9
_cell_length_c   5.9
_cell_angle_alpha   123.66
_cell_angle_beta   123.66
_cell_angle_gamma   83.77
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si(SbSe)2
_chemical_formula_sum   'Si1 Sb2 Se2'
_cell_volume   136.61
_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  Si4  1  0.0  0.0  0.0  1.0
  Sb  Sb0  1  0.0  0.79  0.2  1.0
  Sb  Sb1  1  0.79  0.0  0.2  1.0
  Se  Se2  1  0.0  0.0  0.98  1.0
  Se  Se3  1  0.0  0.0  0.81  1.0

data_Si(SbSe)2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.88
_cell_length_b   7.88
_cell_length_c   5.9
_cell_angle_alpha   90.0
_cell_angle_beta   131.89
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Si(SbSe)2
_chemical_formula_sum   'Si2 Sb4 Se4'
_cell_volume   273.22
_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  0.0  1.0
  Sb  Sb1  4  0.11  0.11  0.41  1.0
  Se  Se2  2  0.0  0.0  0.81  1.0
  Se  Se3  2  0.0  0.0  0.98  1.0

Si Sb Sb Se Se