data_HgGe2Bi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.17
_cell_length_b   5.17
_cell_length_c   5.17
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgGe2Bi
_chemical_formula_sum   'Hg1 Ge2 Bi1'
_cell_volume   97.48
_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  Hg3  1  0.0  0.0  0.0  1.0
  Ge  Ge1  1  0.83  0.83  0.83  1.0
  Ge  Ge2  1  0.48  0.48  0.48  1.0
  Bi  Bi0  1  0.65  0.65  0.65  1.0

data_HgGe2Bi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.17
_cell_length_b   5.17
_cell_length_c   12.65
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   HgGe2Bi
_chemical_formula_sum   'Hg3 Ge6 Bi3'
_cell_volume   292.43
_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  0.0  1.0
  Ge  Ge1  3  0.0  0.0  0.17  1.0
  Ge  Ge2  3  0.0  0.0  0.52  1.0
  Bi  Bi3  3  0.0  0.0  0.35  1.0

Hg Ge Ge Bi
Hg Ge Ge Bi 0 1 - - - 1 3 o o o 2 3 o o o 
HgGe2Bi crystallizes in the trigonal R3m space group. Hg(1) is bonded to one Ge(1) and three equivalent Bi(1) atoms to form HgGeBi3 trigonal pyramids that share  a cornercorner with one Bi(1)Hg3Ge2 trigonal bipyramid and corners with six equivalent Hg(1)GeBi3 trigonal pyramids. The Hg(1)-Ge(1) bond length is 2.20 Å. All Hg(1)-Bi(1) bond lengths are 2.99 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a distorted linear geometry to one Hg(1) and one Bi(1) atom. The Ge(1)-Bi(1) bond length is 2.20 Å. In the second Ge site, Ge(2) is bonded in a distorted single-bond geometry to one Bi(1) atom. The Ge(2)-Bi(1) bond length is 2.20 Å. Bi(1) is bonded to three equivalent Hg(1), one Ge(1), and one Ge(2) atom to form distorted BiHg3Ge2 trigonal bipyramids that share corners with six equivalent Bi(1)Hg3Ge2 trigonal bipyramids and  a cornercorner with one Hg(1)GeBi3 trigonal pyramid.