The compound described by La2HfO5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(4) atoms. In the second La site, La(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form LaO6 octahedra that share corners with two equivalent La(2)O6 octahedra, corners with four equivalent Hf(1)O6 octahedra, and edges with two equivalent La(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-66°. Hf(1) is bonded to one O(3), one O(4), one O(5), and three equivalent O(2) atoms to form HfO6 octahedra that share corners with two equivalent Hf(1)O6 octahedra, corners with four equivalent La(2)O6 octahedra, and edges with two equivalent Hf(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-62°. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent La(1) and two equivalent La(2) atoms to form OLa4 tetrahedra that share corners with two equivalent O(3)La3Hf tetrahedra, corners with four equivalent O(4)La3Hf tetrahedra, corners with four equivalent O(1)La4 tetrahedra,  an edgeedge with one O(4)La3Hf tetrahedra, and edges with two equivalent O(3)La3Hf tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to three equivalent Hf(1) atoms. In the third O site, O(3) is bonded to one La(1), two equivalent La(2), and one Hf(1) atom to form distorted OLa3Hf tetrahedra that share corners with two equivalent O(3)La3Hf tetrahedra, corners with two equivalent O(1)La4 tetrahedra, corners with four equivalent O(4)La3Hf tetrahedra, and edges with two equivalent O(1)La4 tetrahedra. In the fourth O site, O(4) is bonded to three equivalent La(1) and one Hf(1) atom to form OLa3Hf tetrahedra that share corners with two equivalent O(4)La3Hf tetrahedra, corners with four equivalent O(3)La3Hf tetrahedra, corners with four equivalent O(1)La4 tetrahedra,  an edgeedge with one O(1)La4 tetrahedra, and edges with two equivalent O(4)La3Hf tetrahedra. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent La(2) and one Hf(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_La2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.909
_cell_length_b   7.825
_cell_length_c   16.488
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   504.339
_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
  La  La0  1  0.250  0.106  0.083  1.0
  La  La1  1  0.250  0.153  0.742  1.0
  La  La2  1  0.750  0.347  0.242  1.0
  La  La3  1  0.750  0.394  0.583  1.0
  La  La4  1  0.250  0.606  0.417  1.0
  La  La5  1  0.250  0.653  0.758  1.0
  La  La6  1  0.750  0.847  0.258  1.0
  La  La7  1  0.750  0.894  0.917  1.0
  Hf  Hf8  1  0.250  0.110  0.428  1.0
  Hf  Hf9  1  0.750  0.390  0.928  1.0
  Hf  Hf10  1  0.250  0.610  0.072  1.0
  Hf  Hf11  1  0.750  0.890  0.572  1.0
  O  O12  1  0.750  0.085  0.172  1.0
  O  O13  1  0.750  0.076  0.460  1.0
  O  O14  1  0.750  0.109  0.649  1.0
  O  O15  1  0.750  0.159  0.996  1.0
  O  O16  1  0.250  0.259  0.327  1.0
  O  O17  1  0.750  0.241  0.827  1.0
  O  O18  1  0.250  0.341  0.496  1.0
  O  O19  1  0.250  0.391  0.149  1.0
  O  O20  1  0.250  0.424  0.960  1.0
  O  O21  1  0.250  0.415  0.672  1.0
  O  O22  1  0.750  0.585  0.328  1.0
  O  O23  1  0.750  0.576  0.040  1.0
  O  O24  1  0.750  0.609  0.851  1.0
  O  O25  1  0.750  0.659  0.504  1.0
  O  O26  1  0.250  0.759  0.173  1.0
  O  O27  1  0.750  0.741  0.673  1.0
  O  O28  1  0.250  0.841  0.004  1.0
  O  O29  1  0.250  0.891  0.351  1.0
  O  O30  1  0.250  0.924  0.540  1.0
  O  O31  1  0.250  0.915  0.828  1.0
[/CIF]
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The compound described by La2HfO5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(4) atoms. In the second La site, La(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form LaO6 octahedra that share corners with two equivalent La(2)O6 octahedra, corners with four equivalent Hf(1)O6 octahedra, and edges with two equivalent La(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-66°. Hf(1) is bonded to one O(3), one O(4), one O(5), and three equivalent O(2) atoms to form HfO6 octahedra that share corners with two equivalent Hf(1)O6 octahedra, corners with four equivalent La(2)O6 octahedra, and edges with two equivalent Hf(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-62°. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent La(1) and two equivalent La(2) atoms to form OLa4 tetrahedra that share corners with two equivalent O(3)La3Hf tetrahedra, corners with four equivalent O(4)La3Hf tetrahedra, corners with four equivalent O(1)La4 tetrahedra,  an edgeedge with one O(4)La3Hf tetrahedra, and edges with two equivalent O(3)La3Hf tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to three equivalent Hf(1) atoms. In the third O site, O(3) is bonded to one La(1), two equivalent La(2), and one Hf(1) atom to form distorted OLa3Hf tetrahedra that share corners with two equivalent O(3)La3Hf tetrahedra, corners with two equivalent O(1)La4 tetrahedra, corners with four equivalent O(4)La3Hf tetrahedra, and edges with two equivalent O(1)La4 tetrahedra. In the fourth O site, O(4) is bonded to three equivalent La(1) and one Hf(1) atom to form OLa3Hf tetrahedra that share corners with two equivalent O(4)La3Hf tetrahedra, corners with four equivalent O(3)La3Hf tetrahedra, corners with four equivalent O(1)La4 tetrahedra,  an edgeedge with one O(1)La4 tetrahedra, and edges with two equivalent O(4)La3Hf tetrahedra. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent La(2) and one Hf(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_La2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.909
_cell_length_b   7.825
_cell_length_c   16.488
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   504.339
_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
  La  La0  1  0.250  0.106  0.083  1.0
  La  La1  1  0.250  0.153  0.742  1.0
  La  La2  1  0.750  0.347  0.242  1.0
  La  La3  1  0.750  0.394  0.583  1.0
  La  La4  1  0.250  0.606  0.417  1.0
  La  La5  1  0.250  0.653  0.758  1.0
  La  La6  1  0.750  0.847  0.258  1.0
  La  La7  1  0.750  0.894  0.917  1.0
  Hf  Hf8  1  0.250  0.110  0.428  1.0
  Hf  Hf9  1  0.750  0.390  0.928  1.0
  Hf  Hf10  1  0.250  0.610  0.072  1.0
  Hf  Hf11  1  0.750  0.890  0.572  1.0
  O  O12  1  0.750  0.085  0.172  1.0
  O  O13  1  0.750  0.076  0.460  1.0
  O  O14  1  0.750  0.109  0.649  1.0
  O  O15  1  0.750  0.159  0.996  1.0
  O  O16  1  0.250  0.259  0.327  1.0
  O  O17  1  0.750  0.241  0.827  1.0
  O  O18  1  0.250  0.341  0.496  1.0
  O  O19  1  0.250  0.391  0.149  1.0
  O  O20  1  0.250  0.424  0.960  1.0
  O  O21  1  0.250  0.415  0.672  1.0
  O  O22  1  0.750  0.585  0.328  1.0
  O  O23  1  0.750  0.576  0.040  1.0
  O  O24  1  0.750  0.609  0.851  1.0
  O  O25  1  0.750  0.659  0.504  1.0
  O  O26  1  0.250  0.759  0.173  1.0
  O  O27  1  0.750  0.741  0.673  1.0
  O  O28  1  0.250  0.841  0.004  1.0
  O  O29  1  0.250  0.891  0.351  1.0
  O  O30  1  0.250  0.924  0.540  1.0
  O  O31  1  0.250  0.915  0.828  1.0
[/CIF]
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