The compound described by Cs2HfO3 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. In the second Cs site, Cs(2) is bonded to two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms to form distorted CsO7 hexagonal pyramids that share corners with four equivalent Cs(2)O7 hexagonal pyramids,  a cornercorner with one Hf(1)O4 tetrahedra, edges with three equivalent Cs(2)O7 hexagonal pyramids, and edges with four equivalent Hf(1)O4 tetrahedra. Hf(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form HfO4 tetrahedra that share  a cornercorner with one Cs(2)O7 hexagonal pyramid, corners with two equivalent Hf(1)O4 tetrahedra, and edges with four equivalent Cs(2)O7 hexagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Hf(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Cs(1), three equivalent Cs(2), and one Hf(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cs(2), three equivalent Cs(1), and one Hf(1) atom. is represented by the CIF card [CIF]
data_Cs2HfO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.509
_cell_length_b   7.294
_cell_length_c   14.538
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   116.500
_symmetry_Int_Tables_number   1
_cell_volume   617.685
_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
  Cs  Cs0  1  0.052  0.105  0.134  1.0
  Cs  Cs1  1  0.367  0.734  0.071  1.0
  Cs  Cs2  1  0.133  0.266  0.571  1.0
  Cs  Cs3  1  0.448  0.895  0.634  1.0
  Cs  Cs4  1  0.552  0.105  0.366  1.0
  Cs  Cs5  1  0.867  0.734  0.429  1.0
  Cs  Cs6  1  0.633  0.266  0.929  1.0
  Cs  Cs7  1  0.948  0.895  0.866  1.0
  Hf  Hf8  1  0.240  0.480  0.328  1.0
  Hf  Hf9  1  0.260  0.520  0.828  1.0
  Hf  Hf10  1  0.740  0.480  0.172  1.0
  Hf  Hf11  1  0.760  0.520  0.672  1.0
  O  O12  1  0.017  0.534  0.250  1.0
  O  O13  1  0.329  0.658  0.433  1.0
  O  O14  1  0.099  0.197  0.364  1.0
  O  O15  1  0.171  0.342  0.933  1.0
  O  O16  1  0.401  0.803  0.864  1.0
  O  O17  1  0.483  0.466  0.750  1.0
  O  O18  1  0.517  0.534  0.250  1.0
  O  O19  1  0.829  0.658  0.067  1.0
  O  O20  1  0.901  0.803  0.636  1.0
  O  O21  1  0.599  0.197  0.136  1.0
  O  O22  1  0.671  0.342  0.567  1.0
  O  O23  1  0.983  0.466  0.750  1.0
[/CIF]
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The compound described by Cs2HfO3 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. In the second Cs site, Cs(2) is bonded to two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms to form distorted CsO7 hexagonal pyramids that share corners with four equivalent Cs(2)O7 hexagonal pyramids,  a cornercorner with one Hf(1)O4 tetrahedra, edges with three equivalent Cs(2)O7 hexagonal pyramids, and edges with four equivalent Hf(1)O4 tetrahedra. Hf(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form HfO4 tetrahedra that share  a cornercorner with one Cs(2)O7 hexagonal pyramid, corners with two equivalent Hf(1)O4 tetrahedra, and edges with four equivalent Cs(2)O7 hexagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Hf(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Cs(1), three equivalent Cs(2), and one Hf(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cs(2), three equivalent Cs(1), and one Hf(1) atom. is represented by the CIF card [CIF]
data_Cs2HfO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.509
_cell_length_b   7.294
_cell_length_c   14.538
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   116.500
_symmetry_Int_Tables_number   1
_cell_volume   617.685
_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
  Cs  Cs0  1  0.052  0.105  0.134  1.0
  Cs  Cs1  1  0.367  0.734  0.071  1.0
  Cs  Cs2  1  0.133  0.266  0.571  1.0
  Cs  Cs3  1  0.448  0.895  0.634  1.0
  Cs  Cs4  1  0.552  0.105  0.366  1.0
  Cs  Cs5  1  0.867  0.734  0.429  1.0
  Cs  Cs6  1  0.633  0.266  0.929  1.0
  Cs  Cs7  1  0.948  0.895  0.866  1.0
  Hf  Hf8  1  0.240  0.480  0.328  1.0
  Hf  Hf9  1  0.260  0.520  0.828  1.0
  Hf  Hf10  1  0.740  0.480  0.172  1.0
  Hf  Hf11  1  0.760  0.520  0.672  1.0
  O  O12  1  0.017  0.534  0.250  1.0
  O  O13  1  0.329  0.658  0.433  1.0
  O  O14  1  0.099  0.197  0.364  1.0
  O  O15  1  0.171  0.342  0.933  1.0
  O  O16  1  0.401  0.803  0.864  1.0
  O  O17  1  0.483  0.466  0.750  1.0
  O  O18  1  0.517  0.534  0.250  1.0
  O  O19  1  0.829  0.658  0.067  1.0
  O  O20  1  0.901  0.803  0.636  1.0
  O  O21  1  0.599  0.197  0.136  1.0
  O  O22  1  0.671  0.342  0.567  1.0
  O  O23  1  0.983  0.466  0.750  1.0
[/CIF]
.