data_K2HgCl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.78
_cell_length_b   4.78
_cell_length_c   7.04
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K2HgCl
_chemical_formula_sum   'K2 Hg1 Cl1'
_cell_volume   160.57
_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
  K  K2  1  0.0  0.0  0.3  1.0
  K  K3  1  0.39  0.39  0.63  1.0
  Hg  Hg1  1  0.39  0.39  0.11  1.0
  Cl  Cl0  1  0.0  0.0  0.55  1.0

data_K2HgCl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.76
_cell_length_b   6.76
_cell_length_c   7.04
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   K2HgCl
_chemical_formula_sum   'K4 Hg2 Cl2'
_cell_volume   321.14
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  K  K0  2  0.0  0.0  0.3  1.0
  K  K1  2  0.39  0.0  0.63  1.0
  Hg  Hg2  2  0.39  0.0  0.11  1.0
  Cl  Cl3  2  0.0  0.0  0.55  1.0

K K Hg Cl
K2HgCl crystallizes in the monoclinic Cm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a distorted single-bond geometry to three equivalent Hg(1) and one Cl(1) atom. There is one shorter (2.97 Å) and two longer (3.73 Å) K(1)-Hg(1) bond lengths. The K(1)-Cl(1) bond length is 1.76 Å. In the second K site, K(2) is bonded in a 5-coordinate geometry to two equivalent Hg(1) and three equivalent Cl(1) atoms. There is one shorter (3.35 Å) and one longer (3.69 Å) K(2)-Hg(1) bond length. There is one shorter (2.68 Å) and two longer (3.50 Å) K(2)-Cl(1) bond lengths. Hg(1) is bonded in a 5-coordinate geometry to two equivalent K(2) and three equivalent K(1) atoms. Cl(1) is bonded in a 4-coordinate geometry to one K(1) and three equivalent K(2) atoms.