data_Nb2CoHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.92
_cell_length_b   2.92
_cell_length_c   7.94
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Nb2CoHg
_chemical_formula_sum   'Nb2 Co1 Hg1'
_cell_volume   67.74
_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  Nb2  1  0.0  0.0  0.05  1.0
  Nb  Nb3  1  0.46  0.46  0.33  1.0
  Co  Co0  1  0.0  0.0  0.8  1.0
  Hg  Hg1  1  0.46  0.46  0.72  1.0

data_Nb2CoHg
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.13
_cell_length_b   4.13
_cell_length_c   7.94
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Nb2CoHg
_chemical_formula_sum   'Nb4 Co2 Hg2'
_cell_volume   135.49
_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  0.0  0.0  0.05  1.0
  Nb  Nb1  2  0.46  0.0  0.33  1.0
  Co  Co2  2  0.0  0.0  0.8  1.0
  Hg  Hg3  2  0.46  0.0  0.72  1.0

Nb Nb Co Hg
Nb Nb Co Hg 0 2 o o - 0 1 o o o 0 1 o - o 0 1 - o o 0 1 - - o 1 1 + o o 1 1 o + o 1 3 o o o 2 3 - - o 2 3 - o o 2 3 o - o 2 3 o o o 
Nb2CoHg crystallizes in the monoclinic Cm space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a single-bond geometry to four equivalent Nb(2) and one Co(1) atom. There are a spread of Nb(1)-Nb(2) bond distances ranging from 2.87-3.10 Å. The Nb(1)-Co(1) bond length is 1.98 Å. In the second Nb site, Nb(2) is bonded in a 9-coordinate geometry to four equivalent Nb(1), four equivalent Nb(2), and one Hg(1) atom. All Nb(2)-Nb(2) bond lengths are 2.92 Å. The Nb(2)-Hg(1) bond length is 3.15 Å. Co(1) is bonded in a 5-coordinate geometry to one Nb(1) and four equivalent Hg(1) atoms. There are a spread of Co(1)-Hg(1) bond distances ranging from 2.01-2.32 Å. Hg(1) is bonded in a 5-coordinate geometry to one Nb(2) and four equivalent Co(1) atoms.