data_CrCuHg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.77
_cell_length_b   4.77
_cell_length_c   4.77
_cell_angle_alpha   124.2
_cell_angle_beta   124.2
_cell_angle_gamma   82.88
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CrCuHg2
_chemical_formula_sum   'Cr1 Cu1 Hg2'
_cell_volume   71.41
_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
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.0  0.0  0.58  1.0
  Hg  Hg2  1  0.23  0.0  0.79  1.0
  Hg  Hg3  1  0.0  0.23  0.79  1.0

data_CrCuHg2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.32
_cell_length_b   6.32
_cell_length_c   4.77
_cell_angle_alpha   90.0
_cell_angle_beta   131.44
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   CrCuHg2
_chemical_formula_sum   'Cr2 Cu2 Hg4'
_cell_volume   142.83
_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
  Cr  Cr0  2  0.0  0.0  0.0  1.0
  Cu  Cu1  2  0.0  0.0  0.58  1.0
  Hg  Hg2  4  0.38  0.38  0.56  1.0

Cr Cu Hg Hg
CrCuHg2 crystallizes in the monoclinic Cm space group. Cr(1) is bonded in a 6-coordinate geometry to two equivalent Cu(1) and four equivalent Hg(1) atoms. There is one shorter (2.01 Å) and one longer (2.76 Å) Cr(1)-Cu(1) bond length. There are two shorter (1.88 Å) and two longer (3.20 Å) Cr(1)-Hg(1) bond lengths. Cu(1) is bonded in a distorted L-shaped geometry to two equivalent Cr(1) and two equivalent Hg(1) atoms. Both Cu(1)-Hg(1) bond lengths are 1.00 Å. Hg(1) is bonded in a distorted single-bond geometry to two equivalent Cr(1) and one Cu(1) atom.