data_YMgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.77
_cell_length_b   4.89
_cell_length_c   5.43
_cell_angle_alpha   90.0
_cell_angle_beta   109.03
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   YMgSe2
_chemical_formula_sum   'Y1 Mg1 Se2'
_cell_volume   94.64
_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  0.72  0.45  0.18  1.0
  Mg  Mg0  1  0.05  0.0  0.71  1.0
  Se  Se1  1  0.82  0.45  0.33  1.0
  Se  Se2  1  0.64  0.0  0.6  1.0

data_YMgSe2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.77
_cell_length_b   4.89
_cell_length_c   5.43
_cell_angle_alpha   90.0
_cell_angle_beta   109.03
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   YMgSe2
_chemical_formula_sum   'Y1 Mg1 Se2'
_cell_volume   94.64
_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  0.72  0.45  0.18  1.0
  Mg  Mg1  1  0.05  0.0  0.71  1.0
  Se  Se2  1  0.64  0.0  0.6  1.0
  Se  Se3  1  0.82  0.45  0.33  1.0

Y Mg Se Se
Y Mg Se Se 0 2 o o o 1 3 - o o 