data_SiNi2Pb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.27
_cell_length_b   3.27
_cell_length_c   5.83
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiNi2Pb
_chemical_formula_sum   'Si1 Ni2 Pb1'
_cell_volume   62.39
_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  Si3  1  0.0  0.0  0.93  1.0
  Ni  Ni0  1  0.64  0.64  0.58  1.0
  Ni  Ni1  1  0.0  0.0  0.31  1.0
  Pb  Pb2  1  0.64  0.64  0.75  1.0

data_SiNi2Pb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.63
_cell_length_b   4.63
_cell_length_c   5.83
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   SiNi2Pb
_chemical_formula_sum   'Si2 Ni4 Pb2'
_cell_volume   124.77
_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  2  0.0  0.0  0.93  1.0
  Ni  Ni1  2  0.0  0.0  0.31  1.0
  Ni  Ni2  2  0.14  0.5  0.58  1.0
  Pb  Pb3  2  0.14  0.5  0.75  1.0

Si Ni Ni Pb
Si Ni Ni Pb 0 3 - - o 0 2 o o + 1 3 o o o 1 2 + + o 
Ni2PbSi crystallizes in the monoclinic Cm space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a single-bond geometry to three equivalent Ni(2) and one Pb(1) atom. There is one shorter (2.28 Å) and two longer (2.85 Å) Ni(1)-Ni(2) bond lengths. The Ni(1)-Pb(1) bond length is 1.01 Å. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to three equivalent Ni(1) and one Si(1) atom. The Ni(2)-Si(1) bond length is 2.24 Å. Pb(1) is bonded in a 1-coordinate geometry to one Ni(1) and one Si(1) atom. The Pb(1)-Si(1) bond length is 1.98 Å. Si(1) is bonded in a 1-coordinate geometry to one Ni(2) and one Pb(1) atom.