data_HgW
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.8
_cell_length_b   4.93
_cell_length_c   5.3
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgW
_chemical_formula_sum   'Hg2 W2'
_cell_volume   73.17
_cell_formula_units_Z   2
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
  Hg  Hg0  1  0.4  0.0  0.14  1.0
  Hg  Hg1  1  0.0  0.47  0.16  1.0
  W  W2  1  0.4  0.47  0.86  1.0
  W  W3  1  0.0  0.0  0.44  1.0

data_HgW
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.8
_cell_length_b   4.93
_cell_length_c   5.3
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   HgW
_chemical_formula_sum   'Hg2 W2'
_cell_volume   73.17
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  Hg  Hg0  2  0.2  0.77  0.99  1.0
  W  W1  2  0.2  0.23  0.71  1.0

Hg Hg W W
Hg Hg W W 0 3 o o o 0 3 + o o 1 2 - o - 1 2 o o - 