data_HgGe2Pb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.16
_cell_length_b   5.16
_cell_length_c   5.16
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgGe2Pb
_chemical_formula_sum   'Hg1 Ge2 Pb1'
_cell_volume   97.13
_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
  Hg  Hg2  1  0.65  0.65  0.65  1.0
  Ge  Ge0  1  0.0  0.0  0.0  1.0
  Ge  Ge1  1  0.82  0.82  0.82  1.0
  Pb  Pb3  1  0.47  0.47  0.47  1.0

data_HgGe2Pb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.16
_cell_length_b   5.16
_cell_length_c   12.64
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   HgGe2Pb
_chemical_formula_sum   'Hg3 Ge6 Pb3'
_cell_volume   291.38
_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
  Hg  Hg0  3  0.0  0.0  0.35  1.0
  Ge  Ge1  3  0.0  0.0  0.0  1.0
  Ge  Ge2  3  0.0  0.0  0.18  1.0
  Pb  Pb3  3  0.0  0.0  0.53  1.0

Hg Ge Ge Pb
Hg Ge Ge Pb 0 3 o o o 0 2 o o o 1 2 - - - 
HgPbGe2 crystallizes in the trigonal R3m space group. Hg(1) is bonded in a distorted linear geometry to one Pb(1), one Ge(2), and three equivalent Ge(1) atoms. The Hg(1)-Pb(1) bond length is 2.22 Å. The Hg(1)-Ge(2) bond length is 2.22 Å. All Hg(1)-Ge(1) bond lengths are 2.99 Å. Pb(1) is bonded to one Hg(1) and three equivalent Ge(2) atoms to form distorted PbHgGe3 trigonal pyramids that share  a cornercorner with one Ge(2)HgGePb3 trigonal bipyramid, corners with six equivalent Pb(1)HgGe3 trigonal pyramids, and edges with three equivalent Ge(1)Hg3Ge trigonal pyramids. All Pb(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 Hg(1) and one Ge(2) atom to form distorted GeHg3Ge trigonal pyramids that share corners with three equivalent Ge(2)HgGePb3 trigonal bipyramids, corners with six equivalent Ge(1)Hg3Ge trigonal pyramids, and edges with three equivalent Pb(1)HgGe3 trigonal pyramids. The Ge(1)-Ge(2) bond length is 2.22 Å. In the second Ge site, Ge(2) is bonded to one Hg(1), three equivalent Pb(1), and one Ge(1) atom to form GeHgGePb3 trigonal bipyramids that share corners with six equivalent Ge(2)HgGePb3 trigonal bipyramids,  a cornercorner with one Pb(1)HgGe3 trigonal pyramid, and corners with three equivalent Ge(1)Hg3Ge trigonal pyramids.