data_Si(SnAs)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.56
_cell_length_b   5.56
_cell_length_c   5.56
_cell_angle_alpha   116.54
_cell_angle_beta   116.54
_cell_angle_gamma   96.11
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si(SnAs)2
_chemical_formula_sum   'Si1 Sn2 As2'
_cell_volume   127.05
_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  0.0  1.0
  Sn  Sn3  1  0.0  0.92  0.86  1.0
  Sn  Sn4  1  0.92  0.0  0.86  1.0
  As  As0  1  0.0  0.0  0.04  1.0
  As  As1  1  0.0  0.0  0.39  1.0

data_Si(SnAs)2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.43
_cell_length_b   8.27
_cell_length_c   5.56
_cell_angle_alpha   90.0
_cell_angle_beta   131.95
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Si(SnAs)2
_chemical_formula_sum   'Si2 Sn4 As4'
_cell_volume   254.09
_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
  Sn  Sn1  4  0.1  0.04  0.14  1.0
  As  As2  2  0.11  0.5  0.61  1.0
  As  As3  2  0.46  0.5  0.96  1.0

Si Sn Sn As As
Si Sn Sn As As 0 3 o o o 0 1 o - - 0 2 - o - 0 4 o o o 1 2 - + o 3 4 o o o 