data_SnGePb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.08
_cell_length_b   5.08
_cell_length_c   5.08
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SnGePb
_chemical_formula_sum   'Sn1 Ge1 Pb1'
_cell_volume   92.7
_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
  Sn  Sn2  1  0.8  0.8  0.8  1.0
  Ge  Ge0  1  0.0  0.0  0.0  1.0
  Pb  Pb1  1  0.59  0.59  0.59  1.0

data_SnGePb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.08
_cell_length_b   5.08
_cell_length_c   12.44
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SnGePb
_chemical_formula_sum   'Sn3 Ge3 Pb3'
_cell_volume   278.1
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Sn  Sn0  3  0.0  0.0  0.2  1.0
  Ge  Ge1  3  0.0  0.0  0.0  1.0
  Pb  Pb2  3  0.0  0.0  0.41  1.0

Sn Ge Pb
Sn Ge Pb 0 2 o o o 0 2 o + o 0 2 + o o 0 2 o o + 0 1 + + + 0 1 + + o 0 1 o + + 0 1 + o + 1 2 - - o 1 2 - o - 1 2 o - - 
PbSnGe is half-Heusler structured and crystallizes in the trigonal R3m space group. Pb(1) is bonded in a 7-coordinate geometry to four equivalent Sn(1) and three equivalent Ge(1) atoms. There is one shorter (2.54 Å) and three longer (3.35 Å) Pb(1)-Sn(1) bond lengths. All Pb(1)-Ge(1) bond lengths are 3.08 Å. Sn(1) is bonded in a 5-coordinate geometry to four equivalent Pb(1) and one Ge(1) atom. The Sn(1)-Ge(1) bond length is 2.54 Å. Ge(1) is bonded in a 4-coordinate geometry to three equivalent Pb(1) and one Sn(1) atom.