data_Na2SnPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.44
_cell_length_b   5.43
_cell_length_c   6.0
_cell_angle_alpha   90.0
_cell_angle_beta   94.01
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2SnPb
_chemical_formula_sum   'Na2 Sn1 Pb1'
_cell_volume   111.77
_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
  Na  Na0  1  0.85  0.71  0.79  1.0
  Na  Na1  1  0.65  0.0  0.66  1.0
  Sn  Sn3  1  0.91  0.0  0.6  1.0
  Pb  Pb2  1  0.15  0.71  0.9  1.0

data_Na2SnPb
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.44
_cell_length_b   5.43
_cell_length_c   6.0
_cell_angle_alpha   90.0
_cell_angle_beta   94.01
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2SnPb
_chemical_formula_sum   'Na2 Sn1 Pb1'
_cell_volume   111.77
_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
  Na  Na0  1  0.65  0.0  0.66  1.0
  Na  Na1  1  0.85  0.71  0.79  1.0
  Sn  Sn2  1  0.91  0.0  0.6  1.0
  Pb  Pb3  1  0.15  0.71  0.9  1.0

Na Na Sn Pb
Na Na Sn Pb 0 3 + o o 1 2 o o o 