data_[Na16Si2Se12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Si  1.9000  1.1000  0.5400
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Pmn2_1]
_cell_length_a [8.7818]
_cell_length_b [7.9987]
_cell_length_c [11.3469]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [31]
_chemical_formula_structural [Na8SiSe6]
_chemical_formula_sum '[Na16 Si2 Se12]'
_cell_volume [797.0423]
_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
[
  Na  Na0  4  0.1738  0.9916  0.1380  1
  Na  Na1  4  0.1845  0.8243  0.8480  1
  Na  Na2  4  0.1915  0.5631  0.2280  1
  Na  Na3  2  0.0000  0.3097  0.5054  1
  Na  Na4  2  0.0000  0.3622  0.0035  1
  Si  Si5  2  0.0000  0.8006  0.5388  1
  Se  Se6  4  0.2158  0.8115  0.4234  1
  Se  Se7  2  0.0000  0.0285  0.6672  1
  Se  Se8  2  0.0000  0.2630  0.2598  1
  Se  Se9  2  0.0000  0.5765  0.6693  1
  Se  Se10  2  0.0000  0.7195  0.0448  1
]