data_[Na8Si4O12]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Cmc2_1]
_cell_length_a [10.6293]
_cell_length_b [6.1567]
_cell_length_c [4.8757]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [36]
_chemical_formula_structural [Na2SiO3]
_chemical_formula_sum '[Na8 Si4 O12]'
_cell_volume [319.0785]
_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  8  0.1651  0.3389  0.0031  1.0
  Si  Si1  4  0.0000  0.1578  0.5384  1.0
  O  O2  8  0.1297  0.2882  0.4837  1.0
  O  O3  4  0.0000  0.0840  0.8745  1.0
]