The compound described by Gd2HfO5 crystallizes in the orthorhombic Cmcm space group. Gd(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 33°. 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 Gd(1) and one Hf(1) atom. In the second O site, O(2) is bonded to three equivalent Gd(1) and one Hf(1) atom to form OGd3Hf tetrahedra that share  a cornercorner with one O(3)Gd2Hf2 tetrahedra, corners with three equivalent O(2)Gd3Hf tetrahedra, edges with two equivalent O(3)Gd2Hf2 tetrahedra, and edges with two equivalent O(2)Gd3Hf tetrahedra. In the third O site, O(3) is bonded to two equivalent Gd(1) and two equivalent Hf(1) atoms to form distorted OGd2Hf2 tetrahedra that share corners with two equivalent O(3)Gd2Hf2 tetrahedra, corners with two equivalent O(2)Gd3Hf tetrahedra, and edges with four equivalent O(2)Gd3Hf tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.076
_cell_length_b   6.076
_cell_length_c   10.973
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   140.083
_symmetry_Int_Tables_number   1
_cell_volume   259.919
_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
  Gd  Gd0  1  0.861  0.139  0.567  1.0
  Gd  Gd1  1  0.861  0.139  0.933  1.0
  Gd  Gd2  1  0.139  0.861  0.067  1.0
  Gd  Gd3  1  0.139  0.861  0.433  1.0
  Hf  Hf4  1  0.823  0.177  0.250  1.0
  Hf  Hf5  1  0.177  0.823  0.750  1.0
  O  O6  1  0.950  0.050  0.120  1.0
  O  O7  1  0.950  0.050  0.380  1.0
  O  O8  1  0.710  0.290  0.409  1.0
  O  O9  1  0.710  0.290  0.091  1.0
  O  O10  1  0.730  0.270  0.750  1.0
  O  O11  1  0.270  0.730  0.250  1.0
  O  O12  1  0.050  0.950  0.620  1.0
  O  O13  1  0.050  0.950  0.880  1.0
  O  O14  1  0.290  0.710  0.591  1.0
  O  O15  1  0.290  0.710  0.909  1.0
[/CIF]
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The compound described by Gd2HfO5 crystallizes in the orthorhombic Cmcm space group. Gd(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 33°. 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 Gd(1) and one Hf(1) atom. In the second O site, O(2) is bonded to three equivalent Gd(1) and one Hf(1) atom to form OGd3Hf tetrahedra that share  a cornercorner with one O(3)Gd2Hf2 tetrahedra, corners with three equivalent O(2)Gd3Hf tetrahedra, edges with two equivalent O(3)Gd2Hf2 tetrahedra, and edges with two equivalent O(2)Gd3Hf tetrahedra. In the third O site, O(3) is bonded to two equivalent Gd(1) and two equivalent Hf(1) atoms to form distorted OGd2Hf2 tetrahedra that share corners with two equivalent O(3)Gd2Hf2 tetrahedra, corners with two equivalent O(2)Gd3Hf tetrahedra, and edges with four equivalent O(2)Gd3Hf tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2HfO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.076
_cell_length_b   6.076
_cell_length_c   10.973
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   140.083
_symmetry_Int_Tables_number   1
_cell_volume   259.919
_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
  Gd  Gd0  1  0.861  0.139  0.567  1.0
  Gd  Gd1  1  0.861  0.139  0.933  1.0
  Gd  Gd2  1  0.139  0.861  0.067  1.0
  Gd  Gd3  1  0.139  0.861  0.433  1.0
  Hf  Hf4  1  0.823  0.177  0.250  1.0
  Hf  Hf5  1  0.177  0.823  0.750  1.0
  O  O6  1  0.950  0.050  0.120  1.0
  O  O7  1  0.950  0.050  0.380  1.0
  O  O8  1  0.710  0.290  0.409  1.0
  O  O9  1  0.710  0.290  0.091  1.0
  O  O10  1  0.730  0.270  0.750  1.0
  O  O11  1  0.270  0.730  0.250  1.0
  O  O12  1  0.050  0.950  0.620  1.0
  O  O13  1  0.050  0.950  0.880  1.0
  O  O14  1  0.290  0.710  0.591  1.0
  O  O15  1  0.290  0.710  0.909  1.0
[/CIF]
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