The crystal structure described by SiO2 is Low Tridymite-like structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to four equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.911
_cell_length_b   6.911
_cell_length_c   6.419
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   306.598
_cell_formula_units_Z   5
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  0.270  0.000  0.119  1.0
  Si  Si1  1  0.000  0.730  0.881  1.0
  Si  Si2  1  0.000  0.270  0.881  1.0
  Si  Si3  1  0.730  0.000  0.119  1.0
  Si  Si4  1  0.000  0.000  0.500  1.0
  O  O5  1  0.192  0.000  0.356  1.0
  O  O6  1  0.000  0.808  0.644  1.0
  O  O7  1  0.000  0.192  0.644  1.0
  O  O8  1  0.808  0.000  0.356  1.0
  O  O9  1  0.191  0.191  0.000  1.0
  O  O10  1  0.191  0.809  0.000  1.0
  O  O11  1  0.809  0.191  0.000  1.0
  O  O12  1  0.809  0.809  0.000  1.0
  O  O13  1  0.500  0.000  0.120  1.0
  O  O14  1  0.000  0.500  0.880  1.0
[/CIF]
.
The crystal structure described by SiO2 is Low Tridymite-like structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to four equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.911
_cell_length_b   6.911
_cell_length_c   6.419
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   306.598
_cell_formula_units_Z   5
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  0.270  0.000  0.119  1.0
  Si  Si1  1  0.000  0.730  0.881  1.0
  Si  Si2  1  0.000  0.270  0.881  1.0
  Si  Si3  1  0.730  0.000  0.119  1.0
  Si  Si4  1  0.000  0.000  0.500  1.0
  O  O5  1  0.192  0.000  0.356  1.0
  O  O6  1  0.000  0.808  0.644  1.0
  O  O7  1  0.000  0.192  0.644  1.0
  O  O8  1  0.808  0.000  0.356  1.0
  O  O9  1  0.191  0.191  0.000  1.0
  O  O10  1  0.191  0.809  0.000  1.0
  O  O11  1  0.809  0.191  0.000  1.0
  O  O12  1  0.809  0.809  0.000  1.0
  O  O13  1  0.500  0.000  0.120  1.0
  O  O14  1  0.000  0.500  0.880  1.0
[/CIF]
.