data_NiHgCl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.95
_cell_length_b   4.95
_cell_length_c   4.95
_cell_angle_alpha   123.86
_cell_angle_beta   123.86
_cell_angle_gamma   83.43
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NiHgCl2
_chemical_formula_sum   'Ni1 Hg1 Cl2'
_cell_volume   80.11
_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
  Ni  Ni3  1  0.0  0.0  0.0  1.0
  Hg  Hg2  1  0.0  0.0  0.69  1.0
  Cl  Cl0  1  0.33  0.0  0.85  1.0
  Cl  Cl1  1  0.0  0.33  0.85  1.0

data_NiHgCl2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.59
_cell_length_b   6.59
_cell_length_c   4.95
_cell_angle_alpha   90.0
_cell_angle_beta   131.71
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NiHgCl2
_chemical_formula_sum   'Ni2 Hg2 Cl4'
_cell_volume   160.23
_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
  Ni  Ni0  2  0.0  0.0  0.0  1.0
  Hg  Hg1  2  0.31  0.0  0.31  1.0
  Cl  Cl2  4  0.32  0.16  0.48  1.0

Ni Hg Cl Cl
Ni Hg Cl Cl 0 1 o o - 1 3 o o o 1 2 o o o 