The material structure described by La2HfO5 crystallizes in the orthorhombic Cmcm space group. La(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(2) atoms. Hf(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedral tilt angles are 30°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent La(1) and one Hf(1) atom. In the second O site, O(2) is bonded to three equivalent La(1) and one Hf(1) atom to form distorted OLa3Hf tetrahedra that share corners with three equivalent O(2)La3Hf tetrahedra,  a cornercorner with one O(3)La2Hf2 trigonal pyramid, edges with two equivalent O(2)La3Hf tetrahedra, and edges with two equivalent O(3)La2Hf2 trigonal pyramids. In the third O site, O(3) is bonded to two equivalent La(1) and two equivalent Hf(1) atoms to form distorted OLa2Hf2 trigonal pyramids that share corners with two equivalent O(2)La3Hf tetrahedra, corners with two equivalent O(3)La2Hf2 trigonal pyramids, and edges with four equivalent O(2)La3Hf tetrahedra. is represented by the CIF card [CIF]
data_La2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.370
_cell_length_b   6.370
_cell_length_c   11.195
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   141.236
_symmetry_Int_Tables_number   1
_cell_volume   284.465
_cell_formula_units_Z   2
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
  La  La0  1  0.862  0.138  0.571  1.0
  La  La1  1  0.862  0.138  0.929  1.0
  La  La2  1  0.138  0.862  0.071  1.0
  La  La3  1  0.138  0.862  0.429  1.0
  Hf  Hf4  1  0.830  0.170  0.250  1.0
  Hf  Hf5  1  0.170  0.830  0.750  1.0
  O  O6  1  0.949  0.051  0.120  1.0
  O  O7  1  0.717  0.283  0.403  1.0
  O  O8  1  0.949  0.051  0.380  1.0
  O  O9  1  0.717  0.283  0.097  1.0
  O  O10  1  0.717  0.283  0.750  1.0
  O  O11  1  0.283  0.717  0.250  1.0
  O  O12  1  0.051  0.949  0.620  1.0
  O  O13  1  0.051  0.949  0.880  1.0
  O  O14  1  0.283  0.717  0.597  1.0
  O  O15  1  0.283  0.717  0.903  1.0
[/CIF]
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The material structure described by La2HfO5 crystallizes in the orthorhombic Cmcm space group. La(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(2) atoms. Hf(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedral tilt angles are 30°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent La(1) and one Hf(1) atom. In the second O site, O(2) is bonded to three equivalent La(1) and one Hf(1) atom to form distorted OLa3Hf tetrahedra that share corners with three equivalent O(2)La3Hf tetrahedra,  a cornercorner with one O(3)La2Hf2 trigonal pyramid, edges with two equivalent O(2)La3Hf tetrahedra, and edges with two equivalent O(3)La2Hf2 trigonal pyramids. In the third O site, O(3) is bonded to two equivalent La(1) and two equivalent Hf(1) atoms to form distorted OLa2Hf2 trigonal pyramids that share corners with two equivalent O(2)La3Hf tetrahedra, corners with two equivalent O(3)La2Hf2 trigonal pyramids, and edges with four equivalent O(2)La3Hf tetrahedra. is represented by the CIF card [CIF]
data_La2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.370
_cell_length_b   6.370
_cell_length_c   11.195
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   141.236
_symmetry_Int_Tables_number   1
_cell_volume   284.465
_cell_formula_units_Z   2
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
  La  La0  1  0.862  0.138  0.571  1.0
  La  La1  1  0.862  0.138  0.929  1.0
  La  La2  1  0.138  0.862  0.071  1.0
  La  La3  1  0.138  0.862  0.429  1.0
  Hf  Hf4  1  0.830  0.170  0.250  1.0
  Hf  Hf5  1  0.170  0.830  0.750  1.0
  O  O6  1  0.949  0.051  0.120  1.0
  O  O7  1  0.717  0.283  0.403  1.0
  O  O8  1  0.949  0.051  0.380  1.0
  O  O9  1  0.717  0.283  0.097  1.0
  O  O10  1  0.717  0.283  0.750  1.0
  O  O11  1  0.283  0.717  0.250  1.0
  O  O12  1  0.051  0.949  0.620  1.0
  O  O13  1  0.051  0.949  0.880  1.0
  O  O14  1  0.283  0.717  0.597  1.0
  O  O15  1  0.283  0.717  0.903  1.0
[/CIF]
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