data_Na2NbPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.13
_cell_length_b   4.51
_cell_length_c   7.05
_cell_angle_alpha   90.0
_cell_angle_beta   90.14
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2NbPb
_chemical_formula_sum   'Na2 Nb1 Pb1'
_cell_volume   99.35
_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  0.06  0.0  0.02  1.0
  Na  Na1  1  0.53  0.25  0.8  1.0
  Nb  Nb2  1  0.02  0.0  0.72  1.0
  Pb  Pb3  1  0.62  0.25  0.03  1.0

data_Na2NbPb
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.13
_cell_length_b   4.51
_cell_length_c   7.05
_cell_angle_alpha   90.0
_cell_angle_beta   90.14
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2NbPb
_chemical_formula_sum   'Na2 Nb1 Pb1'
_cell_volume   99.35
_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  0.06  0.0  0.02  1.0
  Na  Na1  1  0.53  0.25  0.8  1.0
  Nb  Nb2  1  0.02  0.0  0.72  1.0
  Pb  Pb3  1  0.62  0.25  0.03  1.0

Na Na Nb Pb
Na Na Nb Pb 0 2 o o - 0 3 - o o 0 3 o o o 1 3 o o + 1 2 + o o 1 2 o o o 