The structure described by SiO2 crystallizes in the orthorhombic Ccce 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 120 degrees geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a linear 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. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the CIF file [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.765
_cell_length_b   5.765
_cell_length_c   11.314
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   94.076
_symmetry_Int_Tables_number   1
_cell_volume   375.080
_cell_formula_units_Z   8
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  0.260  0.132  0.121  1.0
  Si  Si1  1  0.368  0.240  0.621  1.0
  Si  Si2  1  0.740  0.868  0.121  1.0
  Si  Si3  1  0.760  0.632  0.379  1.0
  Si  Si4  1  0.632  0.760  0.621  1.0
  Si  Si5  1  0.240  0.368  0.379  1.0
  Si  Si6  1  0.868  0.740  0.879  1.0
  Si  Si7  1  0.132  0.260  0.879  1.0
  O  O8  1  0.289  0.289  0.000  1.0
  O  O9  1  0.500  0.000  0.123  1.0
  O  O10  1  0.000  0.000  0.114  1.0
  O  O11  1  0.250  0.250  0.750  1.0
  O  O12  1  0.711  0.711  0.000  1.0
  O  O13  1  0.500  0.000  0.623  1.0
  O  O14  1  0.000  0.500  0.377  1.0
  O  O15  1  0.500  0.500  0.386  1.0
  O  O16  1  0.789  0.789  0.500  1.0
  O  O17  1  0.250  0.250  0.250  1.0
  O  O18  1  0.750  0.750  0.250  1.0
  O  O19  1  0.211  0.211  0.500  1.0
  O  O20  1  0.500  0.500  0.614  1.0
  O  O21  1  0.000  0.000  0.886  1.0
  O  O22  1  0.000  0.500  0.877  1.0
  O  O23  1  0.750  0.750  0.750  1.0
[/CIF]
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The structure described by SiO2 crystallizes in the orthorhombic Ccce 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 120 degrees geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a linear 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. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the CIF file [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.765
_cell_length_b   5.765
_cell_length_c   11.314
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   94.076
_symmetry_Int_Tables_number   1
_cell_volume   375.080
_cell_formula_units_Z   8
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  0.260  0.132  0.121  1.0
  Si  Si1  1  0.368  0.240  0.621  1.0
  Si  Si2  1  0.740  0.868  0.121  1.0
  Si  Si3  1  0.760  0.632  0.379  1.0
  Si  Si4  1  0.632  0.760  0.621  1.0
  Si  Si5  1  0.240  0.368  0.379  1.0
  Si  Si6  1  0.868  0.740  0.879  1.0
  Si  Si7  1  0.132  0.260  0.879  1.0
  O  O8  1  0.289  0.289  0.000  1.0
  O  O9  1  0.500  0.000  0.123  1.0
  O  O10  1  0.000  0.000  0.114  1.0
  O  O11  1  0.250  0.250  0.750  1.0
  O  O12  1  0.711  0.711  0.000  1.0
  O  O13  1  0.500  0.000  0.623  1.0
  O  O14  1  0.000  0.500  0.377  1.0
  O  O15  1  0.500  0.500  0.386  1.0
  O  O16  1  0.789  0.789  0.500  1.0
  O  O17  1  0.250  0.250  0.250  1.0
  O  O18  1  0.750  0.750  0.250  1.0
  O  O19  1  0.211  0.211  0.500  1.0
  O  O20  1  0.500  0.500  0.614  1.0
  O  O21  1  0.000  0.000  0.886  1.0
  O  O22  1  0.000  0.500  0.877  1.0
  O  O23  1  0.750  0.750  0.750  1.0
[/CIF]
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