The crystal structure described by SiO2 crystallizes in the monoclinic P2 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted see-saw-like geometry to one O(1), one O(2), one O(4), and one O(5) atom. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form corner-sharing SiO4 tetrahedra. There are five 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 one Si(1) and one Si(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to two equivalent Si(2) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a water-like 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   4.281
_cell_length_b   4.318
_cell_length_c   8.003
_cell_angle_alpha   86.378
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   147.642
_cell_formula_units_Z   4
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  0.416  0.553  0.194  1.0
  Si  Si1  1  0.011  0.862  0.679  1.0
  Si  Si2  1  0.011  0.138  0.321  1.0
  Si  Si3  1  0.416  0.447  0.806  1.0
  O  O4  1  0.335  0.500  0.000  1.0
  O  O5  1  0.769  0.372  0.209  1.0
  O  O6  1  0.859  0.000  0.500  1.0
  O  O7  1  0.223  0.891  0.213  1.0
  O  O8  1  0.282  0.377  0.365  1.0
  O  O9  1  0.282  0.623  0.635  1.0
  O  O10  1  0.769  0.628  0.791  1.0
  O  O11  1  0.223  0.109  0.787  1.0
[/CIF]
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The crystal structure described by SiO2 crystallizes in the monoclinic P2 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted see-saw-like geometry to one O(1), one O(2), one O(4), and one O(5) atom. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form corner-sharing SiO4 tetrahedra. There are five 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 one Si(1) and one Si(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to two equivalent Si(2) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a water-like 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   4.281
_cell_length_b   4.318
_cell_length_c   8.003
_cell_angle_alpha   86.378
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   147.642
_cell_formula_units_Z   4
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  0.416  0.553  0.194  1.0
  Si  Si1  1  0.011  0.862  0.679  1.0
  Si  Si2  1  0.011  0.138  0.321  1.0
  Si  Si3  1  0.416  0.447  0.806  1.0
  O  O4  1  0.335  0.500  0.000  1.0
  O  O5  1  0.769  0.372  0.209  1.0
  O  O6  1  0.859  0.000  0.500  1.0
  O  O7  1  0.223  0.891  0.213  1.0
  O  O8  1  0.282  0.377  0.365  1.0
  O  O9  1  0.282  0.623  0.635  1.0
  O  O10  1  0.769  0.628  0.791  1.0
  O  O11  1  0.223  0.109  0.787  1.0
[/CIF]
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