data_SiAs2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.71
_cell_length_b   6.71
_cell_length_c   6.71
_cell_angle_alpha   32.75
_cell_angle_beta   32.75
_cell_angle_gamma   32.75
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiAs2Se
_chemical_formula_sum   'Si1 As2 Se1'
_cell_volume   78.8
_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  Si3  1  0.0  0.0  0.0  1.0
  As  As0  1  0.0  0.0  0.97  1.0
  As  As1  1  0.0  0.0  0.08  1.0
  Se  Se2  1  0.0  0.0  0.52  1.0

data_SiAs2Se
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.56
_cell_length_b   3.79
_cell_length_c   6.71
_cell_angle_alpha   90.0
_cell_angle_beta   109.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   SiAs2Se
_chemical_formula_sum   'Si2 As4 Se2'
_cell_volume   157.61
_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
  As  As1  2  -0.0  0.0  0.92  1.0
  As  As2  2  -0.0  0.0  0.03  1.0
  Se  Se3  2  -0.0  0.0  0.48  1.0

Si As As Se
Si As As Se 0 1 o o - 0 2 o o o 0 3 o o o 0 3 o o - 1 3 o o + 1 3 o o o 2 3 o o o 2 3 o o - 3 3 o + - 3 3 + - o 3 3 + o - 