data_AgHgPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.94
_cell_length_b   4.94
_cell_length_c   4.94
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AgHgPb
_chemical_formula_sum   'Ag1 Hg1 Pb1'
_cell_volume   85.46
_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
  Ag  Ag0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.5  0.5  0.5  1.0
  Pb  Pb2  1  0.24  0.24  0.24  1.0

data_AgHgPb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.94
_cell_length_b   4.94
_cell_length_c   12.11
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   AgHgPb
_chemical_formula_sum   'Ag3 Hg3 Pb3'
_cell_volume   256.39
_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
  Ag  Ag0  3  0.0  0.0  0.0  1.0
  Hg  Hg1  3  0.0  0.0  0.5  1.0
  Pb  Pb2  3  0.0  0.0  0.76  1.0

Ag Hg Pb
Ag Hg Pb 0 2 o - o 0 2 - o o 0 2 o o - 0 2 o o o 0 1 - - o 0 1 - o - 0 1 - o o 0 1 o - - 0 1 o - o 0 1 o o - 1 2 o o o 1 2 o o + 1 2 o + o 1 2 + o o 
AgHgPb is half-Heusler structured and crystallizes in the trigonal R3m space group. Ag(1) is bonded to four equivalent Pb(1) atoms to form AgPb4 tetrahedra that share corners with four equivalent Hg(1)Pb4 tetrahedra, corners with twelve equivalent Ag(1)Pb4 tetrahedra, and edges with six equivalent Hg(1)Pb4 tetrahedra. There is one shorter (2.96 Å) and three longer (3.05 Å) Ag(1)-Pb(1) bond lengths. Hg(1) is bonded to four equivalent Pb(1) atoms to form HgPb4 tetrahedra that share corners with four equivalent Ag(1)Pb4 tetrahedra, corners with twelve equivalent Hg(1)Pb4 tetrahedra, and edges with six equivalent Ag(1)Pb4 tetrahedra. There are three shorter (3.02 Å) and one longer (3.05 Å) Hg(1)-Pb(1) bond length. Pb(1) is bonded in a body-centered cubic geometry to four equivalent Ag(1) and four equivalent Hg(1) atoms.