data_[Si12O24]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Si  1.9000  1.1000  0.5400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pbcn]
_cell_length_a [8.6492]
_cell_length_b [10.1914]
_cell_length_c [4.8250]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [60]
_chemical_formula_structural [SiO2]
_chemical_formula_sum '[Si12 O24]'
_cell_volume [425.3131]
_cell_formula_units_Z [12]
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
[
  Si  Si0  8  0.2057  0.4162  0.0673  1
  Si  Si1  4  0.0000  0.2073  0.7500  1
  O  O2  8  0.1073  0.2923  0.9590  1
  O  O3  8  0.1108  0.1182  0.5523  1
  O  O4  8  0.1649  0.4527  0.3877  1
]