data_SiSn2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.96
_cell_length_b   5.96
_cell_length_c   5.96
_cell_angle_alpha   146.14
_cell_angle_beta   126.46
_cell_angle_gamma   64.87
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiSn2Se
_chemical_formula_sum   'Si1 Sn2 Se1'
_cell_volume   93.58
_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  Si1  1  0.0  0.0  0.31  1.0
  Sn  Sn2  1  0.0  0.68  0.73  1.0
  Sn  Sn3  1  0.0  0.0  0.58  1.0
  Se  Se0  1  0.0  0.68  0.46  1.0

data_SiSn2Se
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.47
_cell_length_b   5.37
_cell_length_c   5.96
_cell_angle_alpha   116.77
_cell_angle_beta   106.93
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiSn2Se
_chemical_formula_sum   'Si1 Sn2 Se1'
_cell_volume   93.58
_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  Si0  1  0.0  0.31  0.31  1.0
  Sn  Sn1  1  0.0  0.58  0.58  1.0
  Sn  Sn2  1  0.32  0.05  0.05  1.0
  Se  Se3  1  0.32  0.78  0.78  1.0

Si Sn Sn Se
Si Sn Sn Se 0 2 o o o 1 3 o o o 2 3 o - o 