The material structure described by Na2Hf2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. Hf(1) is bonded to one O(2) and four equivalent O(1) atoms to form distorted corner-sharing HfO5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Na(1) and two equivalent Hf(1) atoms. In the second O site, O(2) is bonded to four equivalent Na(2) and two equivalent Hf(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Hf2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2Hf2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.948
_cell_length_b   3.950
_cell_length_c   3.950
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   124.005
_cell_formula_units_Z   1
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
  Na  Na0  1  0.000  0.000  0.000  1.0
  Na  Na1  1  0.500  0.000  0.000  1.0
  Hf  Hf2  1  0.252  0.500  0.500  1.0
  Hf  Hf3  1  0.748  0.500  0.500  1.0
  O  O4  1  0.199  0.500  0.000  1.0
  O  O5  1  0.801  0.500  0.000  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.199  0.000  0.500  1.0
  O  O8  1  0.801  0.000  0.500  1.0
[/CIF]
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The material structure described by Na2Hf2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. Hf(1) is bonded to one O(2) and four equivalent O(1) atoms to form distorted corner-sharing HfO5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Na(1) and two equivalent Hf(1) atoms. In the second O site, O(2) is bonded to four equivalent Na(2) and two equivalent Hf(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Hf2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2Hf2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.948
_cell_length_b   3.950
_cell_length_c   3.950
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   124.005
_cell_formula_units_Z   1
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
  Na  Na0  1  0.000  0.000  0.000  1.0
  Na  Na1  1  0.500  0.000  0.000  1.0
  Hf  Hf2  1  0.252  0.500  0.500  1.0
  Hf  Hf3  1  0.748  0.500  0.500  1.0
  O  O4  1  0.199  0.500  0.000  1.0
  O  O5  1  0.801  0.500  0.000  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.199  0.000  0.500  1.0
  O  O8  1  0.801  0.000  0.500  1.0
[/CIF]
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