data_SnGe2Pb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   5.18
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SnGe2Pb
_chemical_formula_sum   'Sn1 Ge2 Pb1'
_cell_volume   98.41
_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  Sn3  1  0.66  0.66  0.66  1.0
  Ge  Ge0  1  0.5  0.5  0.5  1.0
  Ge  Ge1  1  0.0  0.0  0.0  1.0
  Pb  Pb2  1  0.83  0.83  0.83  1.0

data_SnGe2Pb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   12.69
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SnGe2Pb
_chemical_formula_sum   'Sn3 Ge6 Pb3'
_cell_volume   295.22
_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  0.34  1.0
  Ge  Ge1  3  0.0  0.0  0.0  1.0
  Ge  Ge2  3  0.0  0.0  0.5  1.0
  Pb  Pb3  3  0.0  0.0  0.17  1.0

Sn Ge Ge Pb
PbSnGe2 crystallizes in the trigonal R3m space group. Pb(1) is bonded to one Sn(1), one Ge(2), and three equivalent Ge(1) atoms to form distorted PbSnGe4 trigonal bipyramids that share corners with six equivalent Pb(1)SnGe4 trigonal bipyramids and  a cornercorner with one Ge(1)SnPb3 trigonal pyramid. The Pb(1)-Sn(1) bond length is 2.13 Å. The Pb(1)-Ge(2) bond length is 2.13 Å. All Pb(1)-Ge(1) bond lengths are 2.99 Å. Sn(1) is bonded in a 5-coordinate geometry to one Pb(1), one Ge(1), and three equivalent Ge(2) atoms. The Sn(1)-Ge(1) bond length is 2.13 Å. All Sn(1)-Ge(2) bond lengths are 2.99 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to three equivalent Pb(1) and one Sn(1) atom to form GeSnPb3 trigonal pyramids that share  a cornercorner with one Pb(1)SnGe4 trigonal bipyramid and corners with six equivalent Ge(1)SnPb3 trigonal pyramids. In the second Ge site, Ge(2) is bonded in a distorted single-bond geometry to one Pb(1) and three equivalent Sn(1) atoms.