The compound described by SiO2 crystallizes in the orthorhombic Fddd 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(2) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the second O site, O(1) 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 120 degrees 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 Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.933
_cell_length_b   10.669
_cell_length_c   8.104
_cell_angle_alpha   85.946
_cell_angle_beta   55.371
_cell_angle_gamma   38.683
_symmetry_Int_Tables_number   1
_cell_volume   396.035
_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  0.737  0.128  0.891  1.0
  Si  Si1  1  0.513  0.122  0.359  1.0
  Si  Si2  1  0.244  0.891  0.128  1.0
  Si  Si3  1  0.128  0.737  0.244  1.0
  Si  Si4  1  0.006  0.359  0.122  1.0
  Si  Si5  1  0.122  0.513  0.006  1.0
  Si  Si6  1  0.359  0.006  0.513  1.0
  Si  Si7  1  0.891  0.244  0.737  1.0
  O  O8  1  0.338  0.338  0.662  1.0
  O  O9  1  0.050  0.050  0.450  1.0
  O  O10  1  0.912  0.912  0.588  1.0
  O  O11  1  0.379  0.121  0.379  1.0
  O  O12  1  0.121  0.379  0.121  1.0
  O  O13  1  0.662  0.662  0.338  1.0
  O  O14  1  0.871  0.129  0.871  1.0
  O  O15  1  0.450  0.450  0.050  1.0
  O  O16  1  0.800  0.800  0.200  1.0
  O  O17  1  0.125  0.125  0.625  1.0
  O  O18  1  0.129  0.871  0.129  1.0
  O  O19  1  0.588  0.588  0.912  1.0
  O  O20  1  0.200  0.200  0.800  1.0
  O  O21  1  0.125  0.625  0.125  1.0
  O  O22  1  0.625  0.125  0.125  1.0
  O  O23  1  0.125  0.125  0.125  1.0
[/CIF]
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The compound described by SiO2 crystallizes in the orthorhombic Fddd 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(2) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the second O site, O(1) 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 120 degrees 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 Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.933
_cell_length_b   10.669
_cell_length_c   8.104
_cell_angle_alpha   85.946
_cell_angle_beta   55.371
_cell_angle_gamma   38.683
_symmetry_Int_Tables_number   1
_cell_volume   396.035
_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  0.737  0.128  0.891  1.0
  Si  Si1  1  0.513  0.122  0.359  1.0
  Si  Si2  1  0.244  0.891  0.128  1.0
  Si  Si3  1  0.128  0.737  0.244  1.0
  Si  Si4  1  0.006  0.359  0.122  1.0
  Si  Si5  1  0.122  0.513  0.006  1.0
  Si  Si6  1  0.359  0.006  0.513  1.0
  Si  Si7  1  0.891  0.244  0.737  1.0
  O  O8  1  0.338  0.338  0.662  1.0
  O  O9  1  0.050  0.050  0.450  1.0
  O  O10  1  0.912  0.912  0.588  1.0
  O  O11  1  0.379  0.121  0.379  1.0
  O  O12  1  0.121  0.379  0.121  1.0
  O  O13  1  0.662  0.662  0.338  1.0
  O  O14  1  0.871  0.129  0.871  1.0
  O  O15  1  0.450  0.450  0.050  1.0
  O  O16  1  0.800  0.800  0.200  1.0
  O  O17  1  0.125  0.125  0.625  1.0
  O  O18  1  0.129  0.871  0.129  1.0
  O  O19  1  0.588  0.588  0.912  1.0
  O  O20  1  0.200  0.200  0.800  1.0
  O  O21  1  0.125  0.625  0.125  1.0
  O  O22  1  0.625  0.125  0.125  1.0
  O  O23  1  0.125  0.125  0.125  1.0
[/CIF]
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