data_Na2CrSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.78
_cell_length_b   4.78
_cell_length_c   4.04
_cell_angle_alpha   91.61
_cell_angle_beta   91.61
_cell_angle_gamma   107.68
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2CrSe
_chemical_formula_sum   'Na2 Cr1 Se1'
_cell_volume   87.79
_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
  Na  Na1  1  0.31  0.07  0.02  1.0
  Na  Na2  1  0.31  0.93  0.02  1.0
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.82  0.0  0.0  1.0

data_Na2CrSe
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.04
_cell_length_b   4.78
_cell_length_c   4.78
_cell_angle_alpha   107.68
_cell_angle_beta   91.61
_cell_angle_gamma   91.61
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2CrSe
_chemical_formula_sum   'Na2 Cr1 Se1'
_cell_volume   87.79
_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
  Na  Na0  1  0.02  0.31  0.93  1.0
  Na  Na1  1  0.02  0.31  0.07  1.0
  Cr  Cr2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.0  0.82  0.0  1.0

Na Na Cr Se