data_Na2SiPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.19
_cell_length_b   4.84
_cell_length_c   6.25
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2SiPb
_chemical_formula_sum   'Na2 Si1 Pb1'
_cell_volume   96.5
_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  0.59  0.42  0.46  1.0
  Na  Na1  1  0.59  0.42  0.8  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0
  Pb  Pb2  1  0.0  0.0  0.13  1.0

data_Na2SiPb
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.19
_cell_length_b   4.84
_cell_length_c   6.25
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2SiPb
_chemical_formula_sum   'Na2 Si1 Pb1'
_cell_volume   96.5
_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  0.59  0.42  0.46  1.0
  Na  Na1  1  0.59  0.42  0.8  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0
  Pb  Pb3  1  0.0  0.0  0.13  1.0

Na Na Si Pb
Na2PbSi crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one Na(2), two equivalent Na(1), and three equivalent Pb(1) atoms. The Na(1)-Na(2) bond length is 2.14 Å. Both Na(1)-Na(1) bond lengths are 3.19 Å. There are a spread of Na(1)-Pb(1) bond distances ranging from 3.17-3.71 Å. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one Na(1) and three equivalent Si(1) atoms. There are a spread of Na(2)-Si(1) bond distances ranging from 2.72-3.34 Å. Pb(1) is bonded in a single-bond geometry to three equivalent Na(1) and one Si(1) atom. The Pb(1)-Si(1) bond length is 0.79 Å. Si(1) is bonded in a single-bond geometry to three equivalent Na(2) and one Pb(1) atom.