The compound described by SiO2 is Low Tridymite-like structured and crystallizes in the tetragonal I4_1/amd 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 card [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.213
_cell_length_b   10.213
_cell_length_c   10.213
_cell_angle_alpha   139.188
_cell_angle_beta   139.188
_cell_angle_gamma   59.088
_symmetry_Int_Tables_number   1
_cell_volume   450.664
_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  0.434  0.215  0.220  1.0
  Si  Si1  1  0.965  0.245  0.280  1.0
  Si  Si2  1  0.965  0.684  0.720  1.0
  Si  Si3  1  0.316  0.035  0.280  1.0
  Si  Si4  1  0.755  0.035  0.720  1.0
  Si  Si5  1  0.995  0.215  0.780  1.0
  Si  Si6  1  0.785  0.005  0.220  1.0
  Si  Si7  1  0.785  0.566  0.780  1.0
  O  O8  1  0.234  0.234  0.000  1.0
  O  O9  1  0.984  0.484  0.500  1.0
  O  O10  1  0.516  0.016  0.500  1.0
  O  O11  1  0.766  0.766  0.000  1.0
  O  O12  1  0.564  0.064  0.129  1.0
  O  O13  1  0.814  0.186  0.000  1.0
  O  O14  1  0.186  0.814  0.000  1.0
  O  O15  1  0.936  0.436  0.871  1.0
  O  O16  1  0.186  0.186  0.371  1.0
  O  O17  1  0.936  0.064  0.500  1.0
  O  O18  1  0.564  0.436  0.500  1.0
  O  O19  1  0.814  0.814  0.629  1.0
  O  O20  1  0.375  0.125  0.250  1.0
  O  O21  1  0.875  0.125  0.250  1.0
  O  O22  1  0.875  0.625  0.750  1.0
  O  O23  1  0.875  0.125  0.750  1.0
[/CIF]
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The compound described by SiO2 is Low Tridymite-like structured and crystallizes in the tetragonal I4_1/amd 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 card [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.213
_cell_length_b   10.213
_cell_length_c   10.213
_cell_angle_alpha   139.188
_cell_angle_beta   139.188
_cell_angle_gamma   59.088
_symmetry_Int_Tables_number   1
_cell_volume   450.664
_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  0.434  0.215  0.220  1.0
  Si  Si1  1  0.965  0.245  0.280  1.0
  Si  Si2  1  0.965  0.684  0.720  1.0
  Si  Si3  1  0.316  0.035  0.280  1.0
  Si  Si4  1  0.755  0.035  0.720  1.0
  Si  Si5  1  0.995  0.215  0.780  1.0
  Si  Si6  1  0.785  0.005  0.220  1.0
  Si  Si7  1  0.785  0.566  0.780  1.0
  O  O8  1  0.234  0.234  0.000  1.0
  O  O9  1  0.984  0.484  0.500  1.0
  O  O10  1  0.516  0.016  0.500  1.0
  O  O11  1  0.766  0.766  0.000  1.0
  O  O12  1  0.564  0.064  0.129  1.0
  O  O13  1  0.814  0.186  0.000  1.0
  O  O14  1  0.186  0.814  0.000  1.0
  O  O15  1  0.936  0.436  0.871  1.0
  O  O16  1  0.186  0.186  0.371  1.0
  O  O17  1  0.936  0.064  0.500  1.0
  O  O18  1  0.564  0.436  0.500  1.0
  O  O19  1  0.814  0.814  0.629  1.0
  O  O20  1  0.375  0.125  0.250  1.0
  O  O21  1  0.875  0.125  0.250  1.0
  O  O22  1  0.875  0.625  0.750  1.0
  O  O23  1  0.875  0.125  0.750  1.0
[/CIF]
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