The compound described by SiO2 is quartz (alpha)-like structured and crystallizes in the tetragonal I-4m2 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to four equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), and two equivalent O(3) 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 120 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Si(2) atoms. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.194
_cell_length_b   7.915
_cell_length_c   7.194
_cell_angle_alpha   117.030
_cell_angle_beta   90.000
_cell_angle_gamma   117.030
_symmetry_Int_Tables_number   1
_cell_volume   313.785
_cell_formula_units_Z   5
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  0.079  0.158  0.898  1.0
  O  O1  1  0.102  0.842  0.921  1.0
  O  O2  1  0.739  0.842  0.921  1.0
  O  O3  1  0.079  0.158  0.261  1.0
  O  O4  1  0.734  0.467  0.734  1.0
  O  O5  1  0.266  0.533  0.266  1.0
  O  O6  1  0.067  0.500  0.933  1.0
  O  O7  1  0.067  0.500  0.567  1.0
  O  O8  1  0.433  0.500  0.933  1.0
  O  O9  1  0.433  0.500  0.567  1.0
  Si  Si10  1  0.000  0.000  0.000  1.0
  Si  Si11  1  0.994  0.576  0.788  1.0
  Si  Si12  1  0.212  0.424  0.418  1.0
  Si  Si13  1  0.212  0.424  0.006  1.0
  Si  Si14  1  0.582  0.576  0.788  1.0
[/CIF]
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The compound described by SiO2 is quartz (alpha)-like structured and crystallizes in the tetragonal I-4m2 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to four equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), and two equivalent O(3) 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 120 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Si(2) atoms. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.194
_cell_length_b   7.915
_cell_length_c   7.194
_cell_angle_alpha   117.030
_cell_angle_beta   90.000
_cell_angle_gamma   117.030
_symmetry_Int_Tables_number   1
_cell_volume   313.785
_cell_formula_units_Z   5
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  0.079  0.158  0.898  1.0
  O  O1  1  0.102  0.842  0.921  1.0
  O  O2  1  0.739  0.842  0.921  1.0
  O  O3  1  0.079  0.158  0.261  1.0
  O  O4  1  0.734  0.467  0.734  1.0
  O  O5  1  0.266  0.533  0.266  1.0
  O  O6  1  0.067  0.500  0.933  1.0
  O  O7  1  0.067  0.500  0.567  1.0
  O  O8  1  0.433  0.500  0.933  1.0
  O  O9  1  0.433  0.500  0.567  1.0
  Si  Si10  1  0.000  0.000  0.000  1.0
  Si  Si11  1  0.994  0.576  0.788  1.0
  Si  Si12  1  0.212  0.424  0.418  1.0
  Si  Si13  1  0.212  0.424  0.006  1.0
  Si  Si14  1  0.582  0.576  0.788  1.0
[/CIF]
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