The compound described by SiO2 crystallizes in the monoclinic Cc space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Si(2) atoms. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees 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   5.359
_cell_length_b   5.359
_cell_length_c   5.438
_cell_angle_alpha   96.571
_cell_angle_beta   96.571
_cell_angle_gamma   100.274
_symmetry_Int_Tables_number   1
_cell_volume   151.177
_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  0.955  0.053  0.503  1.0
  Si  Si1  1  0.372  0.526  0.083  1.0
  Si  Si2  1  0.526  0.372  0.583  1.0
  Si  Si3  1  0.053  0.955  0.003  1.0
  O  O4  1  0.564  0.489  0.876  1.0
  O  O5  1  0.875  0.903  0.220  1.0
  O  O6  1  0.269  0.783  0.033  1.0
  O  O7  1  0.157  0.263  0.035  1.0
  O  O8  1  0.903  0.875  0.720  1.0
  O  O9  1  0.783  0.269  0.533  1.0
  O  O10  1  0.489  0.564  0.376  1.0
  O  O11  1  0.263  0.157  0.535  1.0
[/CIF]
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The compound described by SiO2 crystallizes in the monoclinic Cc space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Si(2) atoms. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees 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   5.359
_cell_length_b   5.359
_cell_length_c   5.438
_cell_angle_alpha   96.571
_cell_angle_beta   96.571
_cell_angle_gamma   100.274
_symmetry_Int_Tables_number   1
_cell_volume   151.177
_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  0.955  0.053  0.503  1.0
  Si  Si1  1  0.372  0.526  0.083  1.0
  Si  Si2  1  0.526  0.372  0.583  1.0
  Si  Si3  1  0.053  0.955  0.003  1.0
  O  O4  1  0.564  0.489  0.876  1.0
  O  O5  1  0.875  0.903  0.220  1.0
  O  O6  1  0.269  0.783  0.033  1.0
  O  O7  1  0.157  0.263  0.035  1.0
  O  O8  1  0.903  0.875  0.720  1.0
  O  O9  1  0.783  0.269  0.533  1.0
  O  O10  1  0.489  0.564  0.376  1.0
  O  O11  1  0.263  0.157  0.535  1.0
[/CIF]
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