data_Si2PbAu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.33
_cell_length_b   5.33
_cell_length_c   5.33
_cell_angle_alpha   131.75
_cell_angle_beta   131.75
_cell_angle_gamma   70.62
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2PbAu
_chemical_formula_sum   'Si2 Pb1 Au1'
_cell_volume   82.57
_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
  Si  Si2  1  0.0  0.18  0.17  1.0
  Si  Si3  1  0.18  0.0  0.17  1.0
  Pb  Pb1  1  0.0  0.0  0.35  1.0
  Au  Au0  1  0.0  0.0  0.0  1.0

data_Si2PbAu
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.16
_cell_length_b   6.16
_cell_length_c   5.33
_cell_angle_alpha   90.0
_cell_angle_beta   125.31
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Si2PbAu
_chemical_formula_sum   'Si4 Pb2 Au2'
_cell_volume   165.15
_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
  Si  Si0  4  0.41  0.41  0.0  1.0
  Pb  Pb1  2  0.15  0.5  0.65  1.0
  Au  Au2  2  0.0  0.0  0.0  1.0

Si Si Pb Au
AuPbSi2 is Indium-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two AuPbSi2 clusters. Au(1) is bonded in an L-shaped geometry to two equivalent Si(1) atoms. Both Au(1)-Si(1) bond lengths are 0.77 Å. Pb(1) is bonded in a 2-coordinate geometry to two equivalent Si(1) atoms. Both Pb(1)-Si(1) bond lengths are 1.72 Å. Si(1) is bonded in a single-bond geometry to one Au(1) and one Pb(1) atom.