The material described by SiO2 is Anatase-like structured and crystallizes in the tetragonal P4_12_12 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Si(2) atoms. In the second O site, O(2) is bonded in a distorted 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 one Si(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.823
_cell_length_b   9.823
_cell_length_c   9.906
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   955.786
_cell_formula_units_Z   12
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  0.271  0.271  0.000  1.0
  Si  Si1  1  0.011  0.375  0.872  1.0
  Si  Si2  1  0.771  0.229  0.750  1.0
  Si  Si3  1  0.229  0.771  0.250  1.0
  Si  Si4  1  0.989  0.625  0.372  1.0
  Si  Si5  1  0.875  0.489  0.622  1.0
  Si  Si6  1  0.729  0.729  0.500  1.0
  Si  Si7  1  0.625  0.989  0.628  1.0
  Si  Si8  1  0.375  0.011  0.128  1.0
  Si  Si9  1  0.511  0.125  0.878  1.0
  Si  Si10  1  0.489  0.875  0.378  1.0
  Si  Si11  1  0.125  0.511  0.122  1.0
  O  O12  1  0.981  0.485  0.750  1.0
  O  O13  1  0.350  0.784  0.364  1.0
  O  O14  1  0.401  0.248  0.898  1.0
  O  O15  1  0.650  0.216  0.864  1.0
  O  O16  1  0.150  0.284  0.886  1.0
  O  O17  1  0.752  0.599  0.602  1.0
  O  O18  1  0.252  0.901  0.148  1.0
  O  O19  1  0.216  0.650  0.136  1.0
  O  O20  1  0.481  0.015  1.000  1.0
  O  O21  1  0.850  0.716  0.386  1.0
  O  O22  1  0.019  0.515  0.250  1.0
  O  O23  1  0.015  0.481  0.000  1.0
  O  O24  1  0.099  0.748  0.352  1.0
  O  O25  1  0.519  0.985  0.500  1.0
  O  O26  1  0.599  0.752  0.398  1.0
  O  O27  1  0.248  0.401  0.102  1.0
  O  O28  1  0.748  0.099  0.648  1.0
  O  O29  1  0.485  0.981  0.250  1.0
  O  O30  1  0.284  0.150  0.114  1.0
  O  O31  1  0.515  0.019  0.750  1.0
  O  O32  1  0.784  0.350  0.636  1.0
  O  O33  1  0.901  0.252  0.852  1.0
  O  O34  1  0.716  0.850  0.614  1.0
  O  O35  1  0.985  0.519  0.500  1.0
[/CIF]
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The material described by SiO2 is Anatase-like structured and crystallizes in the tetragonal P4_12_12 space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Si(2) atoms. In the second O site, O(2) is bonded in a distorted 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 one Si(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.823
_cell_length_b   9.823
_cell_length_c   9.906
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   955.786
_cell_formula_units_Z   12
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  0.271  0.271  0.000  1.0
  Si  Si1  1  0.011  0.375  0.872  1.0
  Si  Si2  1  0.771  0.229  0.750  1.0
  Si  Si3  1  0.229  0.771  0.250  1.0
  Si  Si4  1  0.989  0.625  0.372  1.0
  Si  Si5  1  0.875  0.489  0.622  1.0
  Si  Si6  1  0.729  0.729  0.500  1.0
  Si  Si7  1  0.625  0.989  0.628  1.0
  Si  Si8  1  0.375  0.011  0.128  1.0
  Si  Si9  1  0.511  0.125  0.878  1.0
  Si  Si10  1  0.489  0.875  0.378  1.0
  Si  Si11  1  0.125  0.511  0.122  1.0
  O  O12  1  0.981  0.485  0.750  1.0
  O  O13  1  0.350  0.784  0.364  1.0
  O  O14  1  0.401  0.248  0.898  1.0
  O  O15  1  0.650  0.216  0.864  1.0
  O  O16  1  0.150  0.284  0.886  1.0
  O  O17  1  0.752  0.599  0.602  1.0
  O  O18  1  0.252  0.901  0.148  1.0
  O  O19  1  0.216  0.650  0.136  1.0
  O  O20  1  0.481  0.015  1.000  1.0
  O  O21  1  0.850  0.716  0.386  1.0
  O  O22  1  0.019  0.515  0.250  1.0
  O  O23  1  0.015  0.481  0.000  1.0
  O  O24  1  0.099  0.748  0.352  1.0
  O  O25  1  0.519  0.985  0.500  1.0
  O  O26  1  0.599  0.752  0.398  1.0
  O  O27  1  0.248  0.401  0.102  1.0
  O  O28  1  0.748  0.099  0.648  1.0
  O  O29  1  0.485  0.981  0.250  1.0
  O  O30  1  0.284  0.150  0.114  1.0
  O  O31  1  0.515  0.019  0.750  1.0
  O  O32  1  0.784  0.350  0.636  1.0
  O  O33  1  0.901  0.252  0.852  1.0
  O  O34  1  0.716  0.850  0.614  1.0
  O  O35  1  0.985  0.519  0.500  1.0
[/CIF]
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