The material described by Ba2HfO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to four equivalent O(1) and five equivalent O(2) atoms. Hf(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent O sites. In the first O site, O(2) is bonded to five equivalent Ba(1) and one Hf(1) atom to form distorted OBa5Hf octahedra that share corners with five equivalent O(2)Ba5Hf octahedra, corners with twelve equivalent O(1)Ba4Hf2 octahedra, edges with eight equivalent O(2)Ba5Hf octahedra, and faces with four equivalent O(1)Ba4Hf2 octahedra. The corner-sharing octahedral tilt angles range from 0-58°. In the second O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Hf(1) atoms to form distorted OBa4Hf2 octahedra that share corners with two equivalent O(1)Ba4Hf2 octahedra, corners with twelve equivalent O(2)Ba5Hf octahedra, edges with two equivalent O(1)Ba4Hf2 octahedra, faces with four equivalent O(1)Ba4Hf2 octahedra, and faces with four equivalent O(2)Ba5Hf octahedra. The corner-sharing octahedral tilt angles range from 0-58°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2HfO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.161
_cell_length_b   4.161
_cell_length_c   7.389
_cell_angle_alpha   73.648
_cell_angle_beta   73.648
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   117.329
_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
  Ba  Ba0  1  0.353  0.353  0.295  1.0
  Ba  Ba1  1  0.647  0.647  0.705  1.0
  Hf  Hf2  1  0.000  0.000  0.000  1.0
  O  O3  1  0.500  0.000  0.000  1.0
  O  O4  1  0.000  0.500  0.000  1.0
  O  O5  1  0.155  0.155  0.691  1.0
  O  O6  1  0.845  0.845  0.309  1.0
[/CIF]
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The material described by Ba2HfO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to four equivalent O(1) and five equivalent O(2) atoms. Hf(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent O sites. In the first O site, O(2) is bonded to five equivalent Ba(1) and one Hf(1) atom to form distorted OBa5Hf octahedra that share corners with five equivalent O(2)Ba5Hf octahedra, corners with twelve equivalent O(1)Ba4Hf2 octahedra, edges with eight equivalent O(2)Ba5Hf octahedra, and faces with four equivalent O(1)Ba4Hf2 octahedra. The corner-sharing octahedral tilt angles range from 0-58°. In the second O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Hf(1) atoms to form distorted OBa4Hf2 octahedra that share corners with two equivalent O(1)Ba4Hf2 octahedra, corners with twelve equivalent O(2)Ba5Hf octahedra, edges with two equivalent O(1)Ba4Hf2 octahedra, faces with four equivalent O(1)Ba4Hf2 octahedra, and faces with four equivalent O(2)Ba5Hf octahedra. The corner-sharing octahedral tilt angles range from 0-58°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2HfO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.161
_cell_length_b   4.161
_cell_length_c   7.389
_cell_angle_alpha   73.648
_cell_angle_beta   73.648
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   117.329
_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
  Ba  Ba0  1  0.353  0.353  0.295  1.0
  Ba  Ba1  1  0.647  0.647  0.705  1.0
  Hf  Hf2  1  0.000  0.000  0.000  1.0
  O  O3  1  0.500  0.000  0.000  1.0
  O  O4  1  0.000  0.500  0.000  1.0
  O  O5  1  0.155  0.155  0.691  1.0
  O  O6  1  0.845  0.845  0.309  1.0
[/CIF]
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