data_SiRu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.9
_cell_length_b   3.49
_cell_length_c   5.29
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiRu
_chemical_formula_sum   'Si2 Ru2'
_cell_volume   53.51
_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
  Si  Si2  1  0.0  0.0  0.76  1.0
  Si  Si3  1  0.45  0.74  0.54  1.0
  Ru  Ru0  1  0.0  0.0  0.59  1.0
  Ru  Ru1  1  0.45  0.74  0.7  1.0

data_SiRu
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.9
_cell_length_b   3.49
_cell_length_c   5.29
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   SiRu
_chemical_formula_sum   'Si2 Ru2'
_cell_volume   53.51
_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
  Si  Si0  2  0.23  0.37  0.39  1.0
  Ru  Ru1  2  0.23  0.37  0.55  1.0

Si Si Ru Ru