data_[Na8Be4Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Be  1.5700  1.0500  0.5900
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [13.8556]
_cell_length_b [5.4511]
_cell_length_c [9.8998]
_cell_angle_alpha [90.0000]
_cell_angle_beta [131.5516]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na2BeSe2]
_chemical_formula_sum '[Na8 Be4 Se8]'
_cell_volume [559.5513]
_cell_formula_units_Z [4]
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  4  0.0781  0.0000  0.7781  1.0
  Na  Na1  4  0.1794  0.5000  0.5228  1.0
  Be  Be2  4  0.1162  0.5000  0.1453  1.0
  Se  Se3  4  0.0517  0.5000  0.8764  1.0
  Se  Se4  4  0.1874  0.0000  0.6142  1.0
]