The material described by SiO2 is beta Tridymite structured and crystallizes in the orthorhombic Ama2 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(3) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.055
_cell_length_b   5.055
_cell_length_c   8.277
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   121.214
_symmetry_Int_Tables_number   1
_cell_volume   180.891
_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  0.340  0.669  0.063  1.0
  Si  Si1  1  0.669  0.340  0.563  1.0
  Si  Si2  1  0.340  0.669  0.437  1.0
  Si  Si3  1  0.669  0.340  0.937  1.0
  O  O4  1  0.603  0.603  0.000  1.0
  O  O5  1  0.465  0.032  0.457  1.0
  O  O6  1  0.574  0.261  0.750  1.0
  O  O7  1  0.032  0.465  0.543  1.0
  O  O8  1  0.261  0.574  0.250  1.0
  O  O9  1  0.032  0.465  0.957  1.0
  O  O10  1  0.603  0.603  0.500  1.0
  O  O11  1  0.465  0.032  0.043  1.0
[/CIF]
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The material described by SiO2 is beta Tridymite structured and crystallizes in the orthorhombic Ama2 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(3) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the third O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.055
_cell_length_b   5.055
_cell_length_c   8.277
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   121.214
_symmetry_Int_Tables_number   1
_cell_volume   180.891
_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  0.340  0.669  0.063  1.0
  Si  Si1  1  0.669  0.340  0.563  1.0
  Si  Si2  1  0.340  0.669  0.437  1.0
  Si  Si3  1  0.669  0.340  0.937  1.0
  O  O4  1  0.603  0.603  0.000  1.0
  O  O5  1  0.465  0.032  0.457  1.0
  O  O6  1  0.574  0.261  0.750  1.0
  O  O7  1  0.032  0.465  0.543  1.0
  O  O8  1  0.261  0.574  0.250  1.0
  O  O9  1  0.032  0.465  0.957  1.0
  O  O10  1  0.603  0.603  0.500  1.0
  O  O11  1  0.465  0.032  0.043  1.0
[/CIF]
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