The structure described by SiO2 is Keatite-like structured and crystallizes in the orthorhombic Imma space group. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are three 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 two equivalent Si(1) atoms. In the third O site, O(3) 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   5.247
_cell_length_b   7.030
_cell_length_c   7.030
_cell_angle_alpha   78.362
_cell_angle_beta   68.091
_cell_angle_gamma   68.091
_symmetry_Int_Tables_number   1
_cell_volume   222.635
_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
  O  O0  1  0.750  0.869  0.131  1.0
  O  O1  1  0.250  0.131  0.869  1.0
  O  O2  1  0.707  0.793  0.793  1.0
  O  O3  1  0.793  0.207  0.207  1.0
  O  O4  1  0.293  0.207  0.207  1.0
  O  O5  1  0.207  0.793  0.793  1.0
  O  O6  1  0.000  0.500  1.000  1.0
  O  O7  1  0.500  0.000  0.500  1.0
  Si  Si8  1  0.915  0.740  0.930  1.0
  Si  Si9  1  0.415  0.930  0.740  1.0
  Si  Si10  1  0.085  0.260  0.070  1.0
  Si  Si11  1  0.585  0.070  0.260  1.0
[/CIF]
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The structure described by SiO2 is Keatite-like structured and crystallizes in the orthorhombic Imma space group. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are three 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 two equivalent Si(1) atoms. In the third O site, O(3) 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   5.247
_cell_length_b   7.030
_cell_length_c   7.030
_cell_angle_alpha   78.362
_cell_angle_beta   68.091
_cell_angle_gamma   68.091
_symmetry_Int_Tables_number   1
_cell_volume   222.635
_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
  O  O0  1  0.750  0.869  0.131  1.0
  O  O1  1  0.250  0.131  0.869  1.0
  O  O2  1  0.707  0.793  0.793  1.0
  O  O3  1  0.793  0.207  0.207  1.0
  O  O4  1  0.293  0.207  0.207  1.0
  O  O5  1  0.207  0.793  0.793  1.0
  O  O6  1  0.000  0.500  1.000  1.0
  O  O7  1  0.500  0.000  0.500  1.0
  Si  Si8  1  0.915  0.740  0.930  1.0
  Si  Si9  1  0.415  0.930  0.740  1.0
  Si  Si10  1  0.085  0.260  0.070  1.0
  Si  Si11  1  0.585  0.070  0.260  1.0
[/CIF]
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