data_Ba2CaHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.67
_cell_length_b   7.67
_cell_length_c   7.67
_cell_angle_alpha   148.23
_cell_angle_beta   131.22
_cell_angle_gamma   59.39
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2CaHg
_chemical_formula_sum   'Ba2 Ca1 Hg1'
_cell_volume   177.02
_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
  Ba  Ba0  1  0.0  0.0  0.98  1.0
  Ba  Ba1  1  0.0  0.17  0.39  1.0
  Ca  Ca2  1  0.0  0.0  0.77  1.0
  Hg  Hg3  1  0.1  0.0  0.18  1.0

data_Ba2CaHg
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.2
_cell_length_b   6.33
_cell_length_c   7.67
_cell_angle_alpha   114.39
_cell_angle_beta   105.88
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2CaHg
_chemical_formula_sum   'Ba2 Ca1 Hg1'
_cell_volume   177.02
_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
  Ba  Ba0  1  0.0  0.98  0.98  1.0
  Ba  Ba1  1  0.83  0.22  0.22  1.0
  Ca  Ca2  1  0.0  0.77  0.77  1.0
  Hg  Hg3  1  0.0  0.18  0.08  1.0

Ba Ba Ca Hg
Ba Ba Ca Hg 0 3 o o + 0 2 o o o 1 3 o o o 
HgBa2Ca crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one HgBa2Ca cluster. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted single-bond geometry to one Ca(1) and one Hg(1) atom. The Ba(1)-Ca(1) bond length is 1.60 Å. The Ba(1)-Hg(1) bond length is 1.21 Å. In the second Ba site, Ba(2) is bonded in a single-bond geometry to one Hg(1) atom. The Ba(2)-Hg(1) bond length is 1.37 Å. Ca(1) is bonded in a single-bond geometry to one Ba(1) atom. Hg(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1) and one Ba(2) atom.