The crystal structure described by SiO2 is quartz (alpha)-like structured and crystallizes in the tetragonal P-4 space group. There are five inequivalent Si sites. In the first Si site, 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. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(4), one O(5), one O(7), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(6), one O(7), one O(8), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the fifth Si site, Si(5) is bonded to four equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are nine inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the second O site, O(6) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom. In the third O site, O(7) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the fourth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the fifth O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(5) atom. In the sixth O site, O(9) is bonded in a bent 150 degrees geometry to two equivalent Si(4) atoms. In the seventh O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the eighth O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the ninth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. is represented by the CIF file [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.074
_cell_length_b   13.074
_cell_length_c   4.993
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   853.466
_cell_formula_units_Z   17
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  0.215  0.049  0.732  1.0
  Si  Si1  1  0.049  0.785  0.268  1.0
  Si  Si2  1  0.951  0.215  0.268  1.0
  Si  Si3  1  0.785  0.951  0.732  1.0
  Si  Si4  1  0.833  0.289  0.766  1.0
  Si  Si5  1  0.289  0.167  0.234  1.0
  Si  Si6  1  0.711  0.833  0.234  1.0
  Si  Si7  1  0.167  0.711  0.766  1.0
  Si  Si8  1  0.652  0.148  0.756  1.0
  Si  Si9  1  0.148  0.348  0.244  1.0
  Si  Si10  1  0.852  0.652  0.244  1.0
  Si  Si11  1  0.348  0.852  0.756  1.0
  Si  Si12  1  0.518  0.116  0.277  1.0
  Si  Si13  1  0.116  0.482  0.723  1.0
  Si  Si14  1  0.884  0.518  0.723  1.0
  Si  Si15  1  0.482  0.884  0.277  1.0
  Si  Si16  1  0.000  0.000  0.500  1.0
  O  O17  1  0.094  0.034  0.690  1.0
  O  O18  1  0.034  0.906  0.310  1.0
  O  O19  1  0.966  0.094  0.310  1.0
  O  O20  1  0.906  0.966  0.690  1.0
  O  O21  1  0.258  0.138  0.538  1.0
  O  O22  1  0.138  0.742  0.462  1.0
  O  O23  1  0.862  0.258  0.462  1.0
  O  O24  1  0.742  0.862  0.538  1.0
  O  O25  1  0.237  0.084  0.038  1.0
  O  O26  1  0.084  0.763  0.962  1.0
  O  O27  1  0.916  0.237  0.962  1.0
  O  O28  1  0.763  0.916  0.038  1.0
  O  O29  1  0.273  0.944  0.665  1.0
  O  O30  1  0.944  0.727  0.335  1.0
  O  O31  1  0.056  0.273  0.335  1.0
  O  O32  1  0.727  0.056  0.665  1.0
  O  O33  1  0.719  0.247  0.833  1.0
  O  O34  1  0.247  0.281  0.167  1.0
  O  O35  1  0.753  0.719  0.167  1.0
  O  O36  1  0.281  0.753  0.833  1.0
  O  O37  1  0.831  0.411  0.798  1.0
  O  O38  1  0.411  0.169  0.202  1.0
  O  O39  1  0.589  0.831  0.202  1.0
  O  O40  1  0.169  0.589  0.798  1.0
  O  O41  1  0.576  0.177  0.513  1.0
  O  O42  1  0.177  0.424  0.487  1.0
  O  O43  1  0.823  0.576  0.487  1.0
  O  O44  1  0.424  0.823  0.513  1.0
  O  O45  1  0.588  0.112  0.013  1.0
  O  O46  1  0.112  0.412  0.987  1.0
  O  O47  1  0.888  0.588  0.987  1.0
  O  O48  1  0.412  0.888  0.013  1.0
  O  O49  1  0.500  0.000  0.382  1.0
  O  O50  1  0.000  0.500  0.618  1.0
[/CIF]
.
The crystal structure described by SiO2 is quartz (alpha)-like structured and crystallizes in the tetragonal P-4 space group. There are five inequivalent Si sites. In the first Si site, 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. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(4), one O(5), one O(7), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(6), one O(7), one O(8), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the fifth Si site, Si(5) is bonded to four equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are nine inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the second O site, O(6) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom. In the third O site, O(7) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the fourth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the fifth O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(5) atom. In the sixth O site, O(9) is bonded in a bent 150 degrees geometry to two equivalent Si(4) atoms. In the seventh O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the eighth O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the ninth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. is represented by the CIF file [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.074
_cell_length_b   13.074
_cell_length_c   4.993
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   853.466
_cell_formula_units_Z   17
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  0.215  0.049  0.732  1.0
  Si  Si1  1  0.049  0.785  0.268  1.0
  Si  Si2  1  0.951  0.215  0.268  1.0
  Si  Si3  1  0.785  0.951  0.732  1.0
  Si  Si4  1  0.833  0.289  0.766  1.0
  Si  Si5  1  0.289  0.167  0.234  1.0
  Si  Si6  1  0.711  0.833  0.234  1.0
  Si  Si7  1  0.167  0.711  0.766  1.0
  Si  Si8  1  0.652  0.148  0.756  1.0
  Si  Si9  1  0.148  0.348  0.244  1.0
  Si  Si10  1  0.852  0.652  0.244  1.0
  Si  Si11  1  0.348  0.852  0.756  1.0
  Si  Si12  1  0.518  0.116  0.277  1.0
  Si  Si13  1  0.116  0.482  0.723  1.0
  Si  Si14  1  0.884  0.518  0.723  1.0
  Si  Si15  1  0.482  0.884  0.277  1.0
  Si  Si16  1  0.000  0.000  0.500  1.0
  O  O17  1  0.094  0.034  0.690  1.0
  O  O18  1  0.034  0.906  0.310  1.0
  O  O19  1  0.966  0.094  0.310  1.0
  O  O20  1  0.906  0.966  0.690  1.0
  O  O21  1  0.258  0.138  0.538  1.0
  O  O22  1  0.138  0.742  0.462  1.0
  O  O23  1  0.862  0.258  0.462  1.0
  O  O24  1  0.742  0.862  0.538  1.0
  O  O25  1  0.237  0.084  0.038  1.0
  O  O26  1  0.084  0.763  0.962  1.0
  O  O27  1  0.916  0.237  0.962  1.0
  O  O28  1  0.763  0.916  0.038  1.0
  O  O29  1  0.273  0.944  0.665  1.0
  O  O30  1  0.944  0.727  0.335  1.0
  O  O31  1  0.056  0.273  0.335  1.0
  O  O32  1  0.727  0.056  0.665  1.0
  O  O33  1  0.719  0.247  0.833  1.0
  O  O34  1  0.247  0.281  0.167  1.0
  O  O35  1  0.753  0.719  0.167  1.0
  O  O36  1  0.281  0.753  0.833  1.0
  O  O37  1  0.831  0.411  0.798  1.0
  O  O38  1  0.411  0.169  0.202  1.0
  O  O39  1  0.589  0.831  0.202  1.0
  O  O40  1  0.169  0.589  0.798  1.0
  O  O41  1  0.576  0.177  0.513  1.0
  O  O42  1  0.177  0.424  0.487  1.0
  O  O43  1  0.823  0.576  0.487  1.0
  O  O44  1  0.424  0.823  0.513  1.0
  O  O45  1  0.588  0.112  0.013  1.0
  O  O46  1  0.112  0.412  0.987  1.0
  O  O47  1  0.888  0.588  0.987  1.0
  O  O48  1  0.412  0.888  0.013  1.0
  O  O49  1  0.500  0.000  0.382  1.0
  O  O50  1  0.000  0.500  0.618  1.0
[/CIF]
.