data_Si3Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.78
_cell_length_b   5.78
_cell_length_c   5.78
_cell_angle_alpha   150.66
_cell_angle_beta   130.22
_cell_angle_gamma   58.84
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si3Hg
_chemical_formula_sum   'Si3 Hg1'
_cell_volume   71.74
_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
  Si  Si1  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.46  0.0  0.14  1.0
  Si  Si3  1  0.0  0.43  0.9  1.0
  Hg  Hg0  1  0.0  0.0  0.04  1.0

data_Si3Hg
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.93
_cell_length_b   4.87
_cell_length_c   5.78
_cell_angle_alpha   114.89
_cell_angle_beta   104.67
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si3Hg
_chemical_formula_sum   'Si3 Hg1'
_cell_volume   71.74
_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
  Si  Si0  1  0.0  0.0  0.0  1.0
  Si  Si1  1  0.0  0.14  0.67  1.0
  Si  Si2  1  0.57  0.46  0.46  1.0
  Hg  Hg3  1  0.0  0.04  0.04  1.0

Si Si Si Hg