The compound described by La2HfO5 crystallizes in the monoclinic C2/c space group. La(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(2), and three equivalent O(1) 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 48°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to three equivalent La(1) and one Hf(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent La(1) and one Hf(1) atom. In the third O site, O(3) is bonded to two equivalent La(1) and two equivalent Hf(1) atoms to form distorted corner-sharing OLa2Hf2 trigonal pyramids. is represented by the CIF file [CIF]
data_La2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.902
_cell_length_b   6.902
_cell_length_c   7.899
_cell_angle_alpha   68.294
_cell_angle_beta   68.294
_cell_angle_gamma   48.415
_symmetry_Int_Tables_number   1
_cell_volume   257.300
_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  0.369  0.343  0.769  1.0
  La  La1  1  0.343  0.369  0.269  1.0
  La  La2  1  0.657  0.631  0.731  1.0
  La  La3  1  0.631  0.657  0.231  1.0
  Hf  Hf4  1  0.000  0.000  0.500  1.0
  Hf  Hf5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.240  0.611  0.967  1.0
  O  O7  1  0.611  0.240  0.467  1.0
  O  O8  1  0.990  0.678  0.634  1.0
  O  O9  1  0.322  0.010  0.866  1.0
  O  O10  1  0.678  0.990  0.134  1.0
  O  O11  1  0.010  0.322  0.366  1.0
  O  O12  1  0.389  0.760  0.533  1.0
  O  O13  1  0.843  0.157  0.750  1.0
  O  O14  1  0.760  0.389  0.033  1.0
  O  O15  1  0.157  0.843  0.250  1.0
[/CIF]
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The compound described by La2HfO5 crystallizes in the monoclinic C2/c space group. La(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(2), and three equivalent O(1) 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 48°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to three equivalent La(1) and one Hf(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent La(1) and one Hf(1) atom. In the third O site, O(3) is bonded to two equivalent La(1) and two equivalent Hf(1) atoms to form distorted corner-sharing OLa2Hf2 trigonal pyramids. is represented by the CIF file [CIF]
data_La2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.902
_cell_length_b   6.902
_cell_length_c   7.899
_cell_angle_alpha   68.294
_cell_angle_beta   68.294
_cell_angle_gamma   48.415
_symmetry_Int_Tables_number   1
_cell_volume   257.300
_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  0.369  0.343  0.769  1.0
  La  La1  1  0.343  0.369  0.269  1.0
  La  La2  1  0.657  0.631  0.731  1.0
  La  La3  1  0.631  0.657  0.231  1.0
  Hf  Hf4  1  0.000  0.000  0.500  1.0
  Hf  Hf5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.240  0.611  0.967  1.0
  O  O7  1  0.611  0.240  0.467  1.0
  O  O8  1  0.990  0.678  0.634  1.0
  O  O9  1  0.322  0.010  0.866  1.0
  O  O10  1  0.678  0.990  0.134  1.0
  O  O11  1  0.010  0.322  0.366  1.0
  O  O12  1  0.389  0.760  0.533  1.0
  O  O13  1  0.843  0.157  0.750  1.0
  O  O14  1  0.760  0.389  0.033  1.0
  O  O15  1  0.157  0.843  0.250  1.0
[/CIF]
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