data_YFeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.49
_cell_length_b   3.49
_cell_length_c   6.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   101.29
_symmetry_Int_Tables_number   1
_chemical_formula_structural   YFeSe2
_chemical_formula_sum   'Y1 Fe1 Se2'
_cell_volume   81.84
_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
  Y  Y3  1  0.0  0.0  0.43  1.0
  Fe  Fe0  1  0.0  0.0  0.0  1.0
  Se  Se1  1  0.21  0.0  0.62  1.0
  Se  Se2  1  0.21  0.0  0.23  1.0

data_YFeSe2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.49
_cell_length_b   3.49
_cell_length_c   6.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   101.29
_symmetry_Int_Tables_number   1
_chemical_formula_structural   YFeSe2
_chemical_formula_sum   'Y1 Fe1 Se2'
_cell_volume   81.84
_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
  Y  Y0  1  0.0  0.0  0.43  1.0
  Fe  Fe1  1  0.0  0.0  0.0  1.0
  Se  Se2  1  0.21  0.0  0.23  1.0
  Se  Se3  1  0.21  0.0  0.62  1.0

Y Fe Se Se
Y Fe Se Se 0 3 o o o 0 2 o o o 1 3 o o o 