data_NbCuHg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.23
_cell_length_b   4.23
_cell_length_c   4.14
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCuHg2
_chemical_formula_sum   'Nb1 Cu1 Hg2'
_cell_volume   73.89
_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
  Nb  Nb3  1  0.11  0.11  0.0  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.0  0.11  0.07  1.0
  Hg  Hg2  1  0.11  0.0  0.07  1.0

data_NbCuHg2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.98
_cell_length_b   5.98
_cell_length_c   4.14
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NbCuHg2
_chemical_formula_sum   'Nb2 Cu2 Hg4'
_cell_volume   147.79
_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
  Nb  Nb0  2  0.11  0.0  0.0  1.0
  Cu  Cu1  2  0.0  0.0  0.0  1.0
  Hg  Hg2  4  0.06  0.06  0.07  1.0

Nb Cu Hg Hg
Nb Cu Hg Hg 0 2 o o o 0 3 o o o 1 3 o o o 1 2 o o o 
NbCuHg2 is alpha Po structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two NbCuHg2 clusters. Nb(1) is bonded in a 3-coordinate geometry to one Cu(1) and two equivalent Hg(1) atoms. The Nb(1)-Cu(1) bond length is 0.67 Å. Both Nb(1)-Hg(1) bond lengths are 0.56 Å. Cu(1) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent Hg(1) atoms. Both Cu(1)-Hg(1) bond lengths are 0.56 Å. Hg(1) is bonded in a 2-coordinate geometry to one Nb(1) and one Cu(1) atom.