data_ZrNbHg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.29
_cell_length_b   5.29
_cell_length_c   5.29
_cell_angle_alpha   131.35
_cell_angle_beta   131.35
_cell_angle_gamma   71.25
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZrNbHg2
_chemical_formula_sum   'Zr1 Nb1 Hg2'
_cell_volume   81.85
_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
  Zr  Zr3  1  0.0  0.0  0.0  1.0
  Nb  Nb2  1  0.0  0.0  0.3  1.0
  Hg  Hg0  1  0.0  0.18  0.15  1.0
  Hg  Hg1  1  0.18  0.0  0.15  1.0

data_ZrNbHg2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.17
_cell_length_b   6.17
_cell_length_c   5.29
_cell_angle_alpha   90.0
_cell_angle_beta   125.63
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   ZrNbHg2
_chemical_formula_sum   'Zr2 Nb2 Hg4'
_cell_volume   163.7
_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
  Zr  Zr0  2  0.0  0.0  0.0  1.0
  Nb  Nb1  2  0.0  0.0  0.3  1.0
  Hg  Hg2  4  0.41  0.41  0.97  1.0

Zr Nb Hg Hg