data_SbPb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.57
_cell_length_b   7.57
_cell_length_c   7.57
_cell_angle_alpha   152.53
_cell_angle_beta   152.53
_cell_angle_gamma   39.24
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SbPb2
_chemical_formula_sum   'Sb1 Pb2'
_cell_volume   91.97
_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
  Sb  Sb2  1  0.0  0.0  0.0  1.0
  Pb  Pb0  1  0.0  0.0  0.42  1.0
  Pb  Pb1  1  0.0  0.0  0.83  1.0

data_SbPb2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.08
_cell_length_b   5.08
_cell_length_c   7.57
_cell_angle_alpha   90.0
_cell_angle_beta   109.62
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   SbPb2
_chemical_formula_sum   'Sb2 Pb4'
_cell_volume   183.95
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Sb  Sb0  2  0.0  0.0  0.0  1.0
  Pb  Pb1  2  0.33  0.5  0.83  1.0
  Pb  Pb2  2  0.42  0.0  0.42  1.0

Sb Pb Pb
Pb2Sb crystallizes in the monoclinic Cm space group. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 6-coordinate geometry to one Pb(2), four equivalent Pb(1), and one Sb(1) atom. The Pb(1)-Pb(2) bond length is 3.11 Å. All Pb(1)-Pb(1) bond lengths are 3.59 Å. The Pb(1)-Sb(1) bond length is 3.19 Å. In the second Pb site, Pb(2) is bonded in a single-bond geometry to one Pb(1) and one Sb(1) atom. The Pb(2)-Sb(1) bond length is 1.27 Å. Sb(1) is bonded in a single-bond geometry to one Pb(1) and one Pb(2) atom.