data_RuSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.89
_cell_length_b   4.89
_cell_length_c   4.48
_cell_angle_alpha   100.71
_cell_angle_beta   100.71
_cell_angle_gamma   36.93
_symmetry_Int_Tables_number   1
_chemical_formula_structural   RuSe
_chemical_formula_sum   'Ru2 Se2'
_cell_volume   63.11
_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
  Ru  Ru0  1  0.02  0.0  0.64  1.0
  Ru  Ru1  1  0.38  0.0  0.75  1.0
  Se  Se2  1  0.53  0.0  0.14  1.0
  Se  Se3  1  0.87  0.0  0.25  1.0

data_RuSe
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.1
_cell_length_b   4.48
_cell_length_c   4.89
_cell_angle_alpha   100.71
_cell_angle_beta   108.47
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   RuSe
_chemical_formula_sum   'Ru2 Se2'
_cell_volume   63.11
_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
  Ru  Ru0  2  0.0  0.45  0.82  1.0
  Se  Se1  2  0.0  0.06  0.67  1.0

Ru Ru Se Se