The material described by Na15Pb4 crystallizes in the cubic I-43d space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to eight equivalent Na(2) and four equivalent Pb(1) atoms to form distorted NaNa8Pb4 cuboctahedra that share corners with eight equivalent Pb(1)Na12 cuboctahedra, edges with eight equivalent Na(1)Na8Pb4 cuboctahedra, and faces with four equivalent Pb(1)Na12 cuboctahedra. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to two equivalent Na(1) and three equivalent Pb(1) atoms. Pb(1) is bonded to three equivalent Na(1) and nine equivalent Na(2) atoms to form distorted PbNa12 cuboctahedra that share corners with six equivalent Na(1)Na8Pb4 cuboctahedra, edges with six equivalent Pb(1)Na12 cuboctahedra, faces with three equivalent Na(1)Na8Pb4 cuboctahedra, and faces with five equivalent Pb(1)Na12 cuboctahedra. is represented by the CIF file [CIF]
data_Na15Pb4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.389
_cell_length_b   11.389
_cell_length_c   11.389
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   1137.135
_cell_formula_units_Z   2
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  0.250  0.625  0.375  1.0
  Na  Na1  1  0.375  0.250  0.625  1.0
  Na  Na2  1  0.125  0.750  0.875  1.0
  Na  Na3  1  0.875  0.125  0.750  1.0
  Na  Na4  1  0.625  0.375  0.250  1.0
  Na  Na5  1  0.750  0.875  0.125  1.0
  Na  Na6  1  0.112  0.084  0.276  1.0
  Na  Na7  1  0.916  0.692  0.029  1.0
  Na  Na8  1  0.163  0.888  0.471  1.0
  Na  Na9  1  0.471  0.163  0.888  1.0
  Na  Na10  1  0.724  0.337  0.808  1.0
  Na  Na11  1  0.808  0.724  0.337  1.0
  Na  Na12  1  0.692  0.029  0.916  1.0
  Na  Na13  1  0.837  0.224  0.308  1.0
  Na  Na14  1  0.529  0.192  0.416  1.0
  Na  Na15  1  0.663  0.971  0.388  1.0
  Na  Na16  1  0.224  0.308  0.837  1.0
  Na  Na17  1  0.416  0.529  0.192  1.0
  Na  Na18  1  0.971  0.388  0.663  1.0
  Na  Na19  1  0.276  0.112  0.084  1.0
  Na  Na20  1  0.084  0.276  0.112  1.0
  Na  Na21  1  0.308  0.837  0.224  1.0
  Na  Na22  1  0.192  0.416  0.529  1.0
  Na  Na23  1  0.388  0.663  0.971  1.0
  Na  Na24  1  0.584  0.612  0.776  1.0
  Na  Na25  1  0.776  0.584  0.612  1.0
  Na  Na26  1  0.612  0.776  0.584  1.0
  Na  Na27  1  0.337  0.808  0.724  1.0
  Na  Na28  1  0.029  0.916  0.692  1.0
  Na  Na29  1  0.888  0.471  0.163  1.0
  Pb  Pb30  1  0.416  0.416  0.416  1.0
  Pb  Pb31  1  0.584  0.500  0.000  1.0
  Pb  Pb32  1  0.000  0.584  0.500  1.0
  Pb  Pb33  1  0.500  0.000  0.584  1.0
  Pb  Pb34  1  0.000  0.084  0.500  1.0
  Pb  Pb35  1  0.500  0.000  0.084  1.0
  Pb  Pb36  1  0.084  0.500  0.000  1.0
  Pb  Pb37  1  0.916  0.916  0.916  1.0
[/CIF]
.
The material described by Na15Pb4 crystallizes in the cubic I-43d space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to eight equivalent Na(2) and four equivalent Pb(1) atoms to form distorted NaNa8Pb4 cuboctahedra that share corners with eight equivalent Pb(1)Na12 cuboctahedra, edges with eight equivalent Na(1)Na8Pb4 cuboctahedra, and faces with four equivalent Pb(1)Na12 cuboctahedra. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to two equivalent Na(1) and three equivalent Pb(1) atoms. Pb(1) is bonded to three equivalent Na(1) and nine equivalent Na(2) atoms to form distorted PbNa12 cuboctahedra that share corners with six equivalent Na(1)Na8Pb4 cuboctahedra, edges with six equivalent Pb(1)Na12 cuboctahedra, faces with three equivalent Na(1)Na8Pb4 cuboctahedra, and faces with five equivalent Pb(1)Na12 cuboctahedra. is represented by the CIF file [CIF]
data_Na15Pb4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.389
_cell_length_b   11.389
_cell_length_c   11.389
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   1137.135
_cell_formula_units_Z   2
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  0.250  0.625  0.375  1.0
  Na  Na1  1  0.375  0.250  0.625  1.0
  Na  Na2  1  0.125  0.750  0.875  1.0
  Na  Na3  1  0.875  0.125  0.750  1.0
  Na  Na4  1  0.625  0.375  0.250  1.0
  Na  Na5  1  0.750  0.875  0.125  1.0
  Na  Na6  1  0.112  0.084  0.276  1.0
  Na  Na7  1  0.916  0.692  0.029  1.0
  Na  Na8  1  0.163  0.888  0.471  1.0
  Na  Na9  1  0.471  0.163  0.888  1.0
  Na  Na10  1  0.724  0.337  0.808  1.0
  Na  Na11  1  0.808  0.724  0.337  1.0
  Na  Na12  1  0.692  0.029  0.916  1.0
  Na  Na13  1  0.837  0.224  0.308  1.0
  Na  Na14  1  0.529  0.192  0.416  1.0
  Na  Na15  1  0.663  0.971  0.388  1.0
  Na  Na16  1  0.224  0.308  0.837  1.0
  Na  Na17  1  0.416  0.529  0.192  1.0
  Na  Na18  1  0.971  0.388  0.663  1.0
  Na  Na19  1  0.276  0.112  0.084  1.0
  Na  Na20  1  0.084  0.276  0.112  1.0
  Na  Na21  1  0.308  0.837  0.224  1.0
  Na  Na22  1  0.192  0.416  0.529  1.0
  Na  Na23  1  0.388  0.663  0.971  1.0
  Na  Na24  1  0.584  0.612  0.776  1.0
  Na  Na25  1  0.776  0.584  0.612  1.0
  Na  Na26  1  0.612  0.776  0.584  1.0
  Na  Na27  1  0.337  0.808  0.724  1.0
  Na  Na28  1  0.029  0.916  0.692  1.0
  Na  Na29  1  0.888  0.471  0.163  1.0
  Pb  Pb30  1  0.416  0.416  0.416  1.0
  Pb  Pb31  1  0.584  0.500  0.000  1.0
  Pb  Pb32  1  0.000  0.584  0.500  1.0
  Pb  Pb33  1  0.500  0.000  0.584  1.0
  Pb  Pb34  1  0.000  0.084  0.500  1.0
  Pb  Pb35  1  0.500  0.000  0.084  1.0
  Pb  Pb36  1  0.084  0.500  0.000  1.0
  Pb  Pb37  1  0.916  0.916  0.916  1.0
[/CIF]
.