The crystal structure described by HfO2 is Baddeleyite-like structured and crystallizes in the orthorhombic Pca2_1 space group. Hf(1) is bonded to three equivalent O(1) and four equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing HfO7 pentagonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to three equivalent Hf(1) atoms. In the second O site, O(2) is bonded to four equivalent Hf(1) atoms to form a mixture of corner and edge-sharing OHf4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.005
_cell_length_b   5.033
_cell_length_c   5.219
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   131.465
_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
  Hf  Hf0  1  0.267  0.241  0.033  1.0
  Hf  Hf1  1  0.267  0.741  0.467  1.0
  Hf  Hf2  1  0.733  0.241  0.533  1.0
  Hf  Hf3  1  0.733  0.741  0.967  1.0
  O  O4  1  0.071  0.379  0.368  1.0
  O  O5  1  0.071  0.879  0.132  1.0
  O  O6  1  0.460  0.492  0.734  1.0
  O  O7  1  0.460  0.992  0.766  1.0
  O  O8  1  0.540  0.992  0.266  1.0
  O  O9  1  0.540  0.492  0.234  1.0
  O  O10  1  0.929  0.379  0.868  1.0
  O  O11  1  0.929  0.879  0.632  1.0
[/CIF]
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The crystal structure described by HfO2 is Baddeleyite-like structured and crystallizes in the orthorhombic Pca2_1 space group. Hf(1) is bonded to three equivalent O(1) and four equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing HfO7 pentagonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to three equivalent Hf(1) atoms. In the second O site, O(2) is bonded to four equivalent Hf(1) atoms to form a mixture of corner and edge-sharing OHf4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.005
_cell_length_b   5.033
_cell_length_c   5.219
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   131.465
_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
  Hf  Hf0  1  0.267  0.241  0.033  1.0
  Hf  Hf1  1  0.267  0.741  0.467  1.0
  Hf  Hf2  1  0.733  0.241  0.533  1.0
  Hf  Hf3  1  0.733  0.741  0.967  1.0
  O  O4  1  0.071  0.379  0.368  1.0
  O  O5  1  0.071  0.879  0.132  1.0
  O  O6  1  0.460  0.492  0.734  1.0
  O  O7  1  0.460  0.992  0.766  1.0
  O  O8  1  0.540  0.992  0.266  1.0
  O  O9  1  0.540  0.492  0.234  1.0
  O  O10  1  0.929  0.379  0.868  1.0
  O  O11  1  0.929  0.879  0.632  1.0
[/CIF]
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