data_CaHgPb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.29
_cell_length_b   6.29
_cell_length_c   6.29
_cell_angle_alpha   136.96
_cell_angle_beta   134.84
_cell_angle_gamma   64.15
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaHgPb2
_chemical_formula_sum   'Ca1 Hg1 Pb2'
_cell_volume   118.75
_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
  Ca  Ca0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.0  0.0  0.33  1.0
  Pb  Pb2  1  0.31  0.0  0.72  1.0
  Pb  Pb3  1  0.0  0.41  0.61  1.0

data_CaHgPb2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.61
_cell_length_b   4.83
_cell_length_c   6.29
_cell_angle_alpha   112.58
_cell_angle_beta   111.52
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaHgPb2
_chemical_formula_sum   'Ca1 Hg1 Pb2'
_cell_volume   118.75
_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
  Ca  Ca0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.67  0.67  0.67  1.0
  Pb  Pb2  1  0.39  0.81  0.81  1.0
  Pb  Pb3  1  0.59  0.28  0.59  1.0

Ca Hg Pb Pb
Ca Hg Pb Pb 0 3 o - - 0 1 o o o 1 3 o o o 1 2 o o o 
CaHgPb2 crystallizes in the triclinic P1 space group. Ca(1) is bonded in a 5-coordinate geometry to one Hg(1), two equivalent Pb(1), and two equivalent Pb(2) atoms. The Ca(1)-Hg(1) bond length is 2.07 Å. There is one shorter (3.36 Å) and one longer (3.40 Å) Ca(1)-Pb(1) bond length. There is one shorter (2.52 Å) and one longer (2.62 Å) Ca(1)-Pb(2) bond length. Hg(1) is bonded in a 3-coordinate geometry to one Ca(1), one Pb(1), and one Pb(2) atom. The Hg(1)-Pb(1) bond length is 1.76 Å. The Hg(1)-Pb(2) bond length is 1.79 Å. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 1-coordinate geometry to two equivalent Ca(1) and one Hg(1) atom. In the second Pb site, Pb(2) is bonded in a 2-coordinate geometry to two equivalent Ca(1) and one Hg(1) atom.