The structure described by SiO2 is Low Tridymite-like structured and crystallizes in the trigonal R-3m space group. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. 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 bent 150 degrees geometry to two equivalent Si(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.278
_cell_length_b   9.278
_cell_length_c   9.278
_cell_angle_alpha   94.235
_cell_angle_beta   94.235
_cell_angle_gamma   94.235
_symmetry_Int_Tables_number   1
_cell_volume   791.792
_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  1  0.333  0.104  0.876  1.0
  Si  Si1  1  0.104  0.876  0.333  1.0
  Si  Si2  1  0.876  0.333  0.104  1.0
  Si  Si3  1  0.124  0.896  0.667  1.0
  Si  Si4  1  0.896  0.667  0.124  1.0
  Si  Si5  1  0.667  0.124  0.896  1.0
  Si  Si6  1  0.667  0.896  0.124  1.0
  Si  Si7  1  0.896  0.124  0.667  1.0
  Si  Si8  1  0.124  0.667  0.896  1.0
  Si  Si9  1  0.876  0.104  0.333  1.0
  Si  Si10  1  0.104  0.333  0.876  1.0
  Si  Si11  1  0.333  0.876  0.104  1.0
  O  O12  1  0.263  0.000  0.737  1.0
  O  O13  1  0.000  0.737  0.263  1.0
  O  O14  1  0.737  0.263  0.000  1.0
  O  O15  1  0.737  0.000  0.263  1.0
  O  O16  1  0.000  0.263  0.737  1.0
  O  O17  1  0.263  0.737  0.000  1.0
  O  O18  1  0.681  0.978  0.978  1.0
  O  O19  1  0.978  0.978  0.681  1.0
  O  O20  1  0.978  0.681  0.978  1.0
  O  O21  1  0.022  0.022  0.319  1.0
  O  O22  1  0.022  0.319  0.022  1.0
  O  O23  1  0.319  0.022  0.022  1.0
  O  O24  1  0.250  0.890  0.250  1.0
  O  O25  1  0.250  0.250  0.890  1.0
  O  O26  1  0.890  0.250  0.250  1.0
  O  O27  1  0.110  0.750  0.750  1.0
  O  O28  1  0.750  0.110  0.750  1.0
  O  O29  1  0.750  0.750  0.110  1.0
  O  O30  1  0.500  0.853  0.147  1.0
  O  O31  1  0.147  0.500  0.853  1.0
  O  O32  1  0.853  0.147  0.500  1.0
  O  O33  1  0.500  0.147  0.853  1.0
  O  O34  1  0.853  0.500  0.147  1.0
  O  O35  1  0.147  0.853  0.500  1.0
[/CIF]
.
The structure described by SiO2 is Low Tridymite-like structured and crystallizes in the trigonal R-3m space group. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. 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 bent 150 degrees geometry to two equivalent Si(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.278
_cell_length_b   9.278
_cell_length_c   9.278
_cell_angle_alpha   94.235
_cell_angle_beta   94.235
_cell_angle_gamma   94.235
_symmetry_Int_Tables_number   1
_cell_volume   791.792
_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  1  0.333  0.104  0.876  1.0
  Si  Si1  1  0.104  0.876  0.333  1.0
  Si  Si2  1  0.876  0.333  0.104  1.0
  Si  Si3  1  0.124  0.896  0.667  1.0
  Si  Si4  1  0.896  0.667  0.124  1.0
  Si  Si5  1  0.667  0.124  0.896  1.0
  Si  Si6  1  0.667  0.896  0.124  1.0
  Si  Si7  1  0.896  0.124  0.667  1.0
  Si  Si8  1  0.124  0.667  0.896  1.0
  Si  Si9  1  0.876  0.104  0.333  1.0
  Si  Si10  1  0.104  0.333  0.876  1.0
  Si  Si11  1  0.333  0.876  0.104  1.0
  O  O12  1  0.263  0.000  0.737  1.0
  O  O13  1  0.000  0.737  0.263  1.0
  O  O14  1  0.737  0.263  0.000  1.0
  O  O15  1  0.737  0.000  0.263  1.0
  O  O16  1  0.000  0.263  0.737  1.0
  O  O17  1  0.263  0.737  0.000  1.0
  O  O18  1  0.681  0.978  0.978  1.0
  O  O19  1  0.978  0.978  0.681  1.0
  O  O20  1  0.978  0.681  0.978  1.0
  O  O21  1  0.022  0.022  0.319  1.0
  O  O22  1  0.022  0.319  0.022  1.0
  O  O23  1  0.319  0.022  0.022  1.0
  O  O24  1  0.250  0.890  0.250  1.0
  O  O25  1  0.250  0.250  0.890  1.0
  O  O26  1  0.890  0.250  0.250  1.0
  O  O27  1  0.110  0.750  0.750  1.0
  O  O28  1  0.750  0.110  0.750  1.0
  O  O29  1  0.750  0.750  0.110  1.0
  O  O30  1  0.500  0.853  0.147  1.0
  O  O31  1  0.147  0.500  0.853  1.0
  O  O32  1  0.853  0.147  0.500  1.0
  O  O33  1  0.500  0.147  0.853  1.0
  O  O34  1  0.853  0.500  0.147  1.0
  O  O35  1  0.147  0.853  0.500  1.0
[/CIF]
.