data_[Si4O8]
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 [P1]
_cell_length_a [4.9266]
_cell_length_b [7.0554]
_cell_length_c [7.1502]
_cell_angle_alpha [114.0621]
_cell_angle_beta [104.0731]
_cell_angle_gamma [102.2258]
_symmetry_Int_Tables_number [1]
_chemical_formula_structural [SiO2]
_chemical_formula_sum '[Si4 O8]'
_cell_volume [206.1197]
_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
[
  Si  Si0  1  0.4370  0.1444  0.5288  1.0
  Si  Si1  1  0.4516  0.8723  0.7724  1.0
  Si  Si2  1  0.8153  0.1599  0.2838  1.0
  Si  Si3  1  0.8170  0.5693  0.6320  1.0
  O  O4  1  0.1507  0.1621  0.3760  1.0
  O  O5  1  0.1640  0.7262  0.7912  1.0
  O  O6  1  0.3367  0.0070  0.6496  1.0
  O  O7  1  0.6036  0.0245  0.3668  1.0
  O  O8  1  0.6099  0.7202  0.6287  1.0
  O  O9  1  0.6747  0.3970  0.7131  1.0
  O  O10  1  0.6967  0.0452  0.0182  1.0
  O  O11  1  0.8114  0.4148  0.3843  1.0
]