data_Si2SnBi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.02
_cell_length_b   5.02
_cell_length_c   3.59
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2SnBi
_chemical_formula_sum   'Si2 Sn1 Bi1'
_cell_volume   90.55
_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  0.51  0.0  0.8  1.0
  Si  Si2  1  0.0  0.51  0.8  1.0
  Sn  Sn3  1  0.0  0.0  0.0  1.0
  Bi  Bi0  1  0.51  0.51  0.0  1.0

data_Si2SnBi
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.1
_cell_length_b   7.1
_cell_length_c   3.59
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Si2SnBi
_chemical_formula_sum   'Si4 Sn2 Bi2'
_cell_volume   181.11
_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  4  0.25  0.25  0.8  1.0
  Sn  Sn1  2  0.0  0.0  0.0  1.0
  Bi  Bi2  2  0.01  0.5  0.0  1.0

Si Si Sn Bi
Si Si Sn Bi 0 2 o o + 0 2 + o + 0 3 o - + 0 3 o o + 1 3 - o + 1 3 o o + 1 2 o o + 1 2 o + + 