The crystal structure described by SiO2 is Keatite-like structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to four equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are two 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 linear geometry to one Si(1) and one Si(2) atom. is represented by the CIF card [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.603
_cell_length_b   9.603
_cell_length_c   9.603
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   626.094
_cell_formula_units_Z   10
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  0.114  0.114  0.114  1.0
  Si  Si1  1  0.886  0.343  0.886  1.0
  Si  Si2  1  0.886  0.886  0.343  1.0
  Si  Si3  1  0.343  0.886  0.886  1.0
  Si  Si4  1  0.114  0.114  0.657  1.0
  Si  Si5  1  0.657  0.114  0.114  1.0
  Si  Si6  1  0.114  0.657  0.114  1.0
  Si  Si7  1  0.886  0.886  0.886  1.0
  Si  Si8  1  0.750  0.750  0.750  1.0
  Si  Si9  1  0.250  0.250  0.250  1.0
  O  O10  1  0.000  0.000  0.275  1.0
  O  O11  1  0.000  0.275  0.000  1.0
  O  O12  1  0.725  0.000  0.275  1.0
  O  O13  1  0.000  0.725  0.275  1.0
  O  O14  1  0.275  0.000  0.000  1.0
  O  O15  1  0.275  0.725  0.000  1.0
  O  O16  1  0.725  0.275  0.000  1.0
  O  O17  1  0.275  0.000  0.725  1.0
  O  O18  1  0.725  0.000  0.000  1.0
  O  O19  1  0.000  0.725  0.000  1.0
  O  O20  1  0.000  0.275  0.725  1.0
  O  O21  1  0.000  0.000  0.725  1.0
  O  O22  1  0.182  0.182  0.182  1.0
  O  O23  1  0.818  0.546  0.818  1.0
  O  O24  1  0.818  0.818  0.546  1.0
  O  O25  1  0.546  0.818  0.818  1.0
  O  O26  1  0.182  0.182  0.454  1.0
  O  O27  1  0.454  0.182  0.182  1.0
  O  O28  1  0.182  0.454  0.182  1.0
  O  O29  1  0.818  0.818  0.818  1.0
[/CIF]
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The crystal structure described by SiO2 is Keatite-like structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to four equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are two 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 linear geometry to one Si(1) and one Si(2) atom. is represented by the CIF card [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.603
_cell_length_b   9.603
_cell_length_c   9.603
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   626.094
_cell_formula_units_Z   10
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  0.114  0.114  0.114  1.0
  Si  Si1  1  0.886  0.343  0.886  1.0
  Si  Si2  1  0.886  0.886  0.343  1.0
  Si  Si3  1  0.343  0.886  0.886  1.0
  Si  Si4  1  0.114  0.114  0.657  1.0
  Si  Si5  1  0.657  0.114  0.114  1.0
  Si  Si6  1  0.114  0.657  0.114  1.0
  Si  Si7  1  0.886  0.886  0.886  1.0
  Si  Si8  1  0.750  0.750  0.750  1.0
  Si  Si9  1  0.250  0.250  0.250  1.0
  O  O10  1  0.000  0.000  0.275  1.0
  O  O11  1  0.000  0.275  0.000  1.0
  O  O12  1  0.725  0.000  0.275  1.0
  O  O13  1  0.000  0.725  0.275  1.0
  O  O14  1  0.275  0.000  0.000  1.0
  O  O15  1  0.275  0.725  0.000  1.0
  O  O16  1  0.725  0.275  0.000  1.0
  O  O17  1  0.275  0.000  0.725  1.0
  O  O18  1  0.725  0.000  0.000  1.0
  O  O19  1  0.000  0.725  0.000  1.0
  O  O20  1  0.000  0.275  0.725  1.0
  O  O21  1  0.000  0.000  0.725  1.0
  O  O22  1  0.182  0.182  0.182  1.0
  O  O23  1  0.818  0.546  0.818  1.0
  O  O24  1  0.818  0.818  0.546  1.0
  O  O25  1  0.546  0.818  0.818  1.0
  O  O26  1  0.182  0.182  0.454  1.0
  O  O27  1  0.454  0.182  0.182  1.0
  O  O28  1  0.182  0.454  0.182  1.0
  O  O29  1  0.818  0.818  0.818  1.0
[/CIF]
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