data_Si2GePb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.28
_cell_length_b   5.28
_cell_length_c   3.2
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   107.48
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2GePb
_chemical_formula_sum   'Si2 Ge1 Pb1'
_cell_volume   84.84
_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  0.56  0.87  0.6  1.0
  Si  Si3  1  0.56  0.13  0.6  1.0
  Ge  Ge0  1  0.0  0.0  0.0  1.0
  Pb  Pb1  1  0.12  0.0  0.0  1.0

data_Si2GePb
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.2
_cell_length_b   5.28
_cell_length_c   5.28
_cell_angle_alpha   107.48
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2GePb
_chemical_formula_sum   'Si2 Ge1 Pb1'
_cell_volume   84.84
_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  0.6  0.56  0.13  1.0
  Si  Si1  1  0.6  0.56  0.87  1.0
  Ge  Ge2  1  0.0  0.0  0.0  1.0
  Pb  Pb3  1  0.0  0.12  0.0  1.0

Si Si Ge Pb
Si Si Ge Pb 0 1 o + o 2 3 o o o 