The structure described by Cs4HfO4 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(2), and three equivalent O(1) atoms. In the second Cs site, Cs(2) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. In the third Cs site, Cs(3) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form distorted CsO4 tetrahedra that share corners with four equivalent Hf(1)O4 tetrahedra and  an edgeedge with one Cs(3)O4 tetrahedra. In the fourth Cs site, Cs(4) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), and two equivalent O(4) atoms. Hf(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form HfO4 tetrahedra that share corners with four equivalent Cs(3)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 1-coordinate geometry to two equivalent Cs(2), three equivalent Cs(1), and one Hf(1) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Cs(2), one Cs(3), one Cs(4), two equivalent Cs(1), and one Hf(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Cs(1), one Cs(2), one Cs(3), two equivalent Cs(4), and one Hf(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Cs(2), two equivalent Cs(3), two equivalent Cs(4), and one Hf(1) atom. is represented by the CIF card [CIF]
data_Cs4HfO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.373
_cell_length_b   11.783
_cell_length_c   11.803
_cell_angle_alpha   68.285
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   952.622
_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  0.587  0.299  0.062  1.0
  Cs  Cs1  1  0.114  0.415  0.157  1.0
  Cs  Cs2  1  0.913  0.799  0.062  1.0
  Cs  Cs3  1  0.340  0.108  0.369  1.0
  Cs  Cs4  1  0.386  0.915  0.157  1.0
  Cs  Cs5  1  0.826  0.207  0.428  1.0
  Cs  Cs6  1  0.160  0.608  0.369  1.0
  Cs  Cs7  1  0.326  0.293  0.572  1.0
  Cs  Cs8  1  0.674  0.707  0.428  1.0
  Cs  Cs9  1  0.840  0.392  0.631  1.0
  Cs  Cs10  1  0.174  0.793  0.572  1.0
  Cs  Cs11  1  0.614  0.085  0.843  1.0
  Cs  Cs12  1  0.660  0.892  0.631  1.0
  Cs  Cs13  1  0.087  0.201  0.938  1.0
  Cs  Cs14  1  0.886  0.585  0.843  1.0
  Cs  Cs15  1  0.413  0.701  0.938  1.0
  Hf  Hf16  1  0.875  0.008  0.242  1.0
  Hf  Hf17  1  0.625  0.508  0.242  1.0
  Hf  Hf18  1  0.375  0.492  0.758  1.0
  Hf  Hf19  1  0.125  0.992  0.758  1.0
  O  O20  1  0.769  0.022  0.086  1.0
  O  O21  1  0.011  0.158  0.218  1.0
  O  O22  1  0.731  0.522  0.086  1.0
  O  O23  1  0.471  0.362  0.304  1.0
  O  O24  1  0.489  0.658  0.218  1.0
  O  O25  1  0.820  0.489  0.360  1.0
  O  O26  1  0.029  0.862  0.304  1.0
  O  O27  1  0.320  0.011  0.640  1.0
  O  O28  1  0.680  0.989  0.360  1.0
  O  O29  1  0.971  0.138  0.696  1.0
  O  O30  1  0.180  0.511  0.640  1.0
  O  O31  1  0.511  0.342  0.782  1.0
  O  O32  1  0.529  0.638  0.696  1.0
  O  O33  1  0.269  0.478  0.914  1.0
  O  O34  1  0.989  0.842  0.782  1.0
  O  O35  1  0.231  0.978  0.914  1.0
[/CIF]
.
The structure described by Cs4HfO4 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(2), and three equivalent O(1) atoms. In the second Cs site, Cs(2) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. In the third Cs site, Cs(3) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form distorted CsO4 tetrahedra that share corners with four equivalent Hf(1)O4 tetrahedra and  an edgeedge with one Cs(3)O4 tetrahedra. In the fourth Cs site, Cs(4) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), and two equivalent O(4) atoms. Hf(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form HfO4 tetrahedra that share corners with four equivalent Cs(3)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 1-coordinate geometry to two equivalent Cs(2), three equivalent Cs(1), and one Hf(1) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Cs(2), one Cs(3), one Cs(4), two equivalent Cs(1), and one Hf(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Cs(1), one Cs(2), one Cs(3), two equivalent Cs(4), and one Hf(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Cs(2), two equivalent Cs(3), two equivalent Cs(4), and one Hf(1) atom. is represented by the CIF card [CIF]
data_Cs4HfO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.373
_cell_length_b   11.783
_cell_length_c   11.803
_cell_angle_alpha   68.285
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   952.622
_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  0.587  0.299  0.062  1.0
  Cs  Cs1  1  0.114  0.415  0.157  1.0
  Cs  Cs2  1  0.913  0.799  0.062  1.0
  Cs  Cs3  1  0.340  0.108  0.369  1.0
  Cs  Cs4  1  0.386  0.915  0.157  1.0
  Cs  Cs5  1  0.826  0.207  0.428  1.0
  Cs  Cs6  1  0.160  0.608  0.369  1.0
  Cs  Cs7  1  0.326  0.293  0.572  1.0
  Cs  Cs8  1  0.674  0.707  0.428  1.0
  Cs  Cs9  1  0.840  0.392  0.631  1.0
  Cs  Cs10  1  0.174  0.793  0.572  1.0
  Cs  Cs11  1  0.614  0.085  0.843  1.0
  Cs  Cs12  1  0.660  0.892  0.631  1.0
  Cs  Cs13  1  0.087  0.201  0.938  1.0
  Cs  Cs14  1  0.886  0.585  0.843  1.0
  Cs  Cs15  1  0.413  0.701  0.938  1.0
  Hf  Hf16  1  0.875  0.008  0.242  1.0
  Hf  Hf17  1  0.625  0.508  0.242  1.0
  Hf  Hf18  1  0.375  0.492  0.758  1.0
  Hf  Hf19  1  0.125  0.992  0.758  1.0
  O  O20  1  0.769  0.022  0.086  1.0
  O  O21  1  0.011  0.158  0.218  1.0
  O  O22  1  0.731  0.522  0.086  1.0
  O  O23  1  0.471  0.362  0.304  1.0
  O  O24  1  0.489  0.658  0.218  1.0
  O  O25  1  0.820  0.489  0.360  1.0
  O  O26  1  0.029  0.862  0.304  1.0
  O  O27  1  0.320  0.011  0.640  1.0
  O  O28  1  0.680  0.989  0.360  1.0
  O  O29  1  0.971  0.138  0.696  1.0
  O  O30  1  0.180  0.511  0.640  1.0
  O  O31  1  0.511  0.342  0.782  1.0
  O  O32  1  0.529  0.638  0.696  1.0
  O  O33  1  0.269  0.478  0.914  1.0
  O  O34  1  0.989  0.842  0.782  1.0
  O  O35  1  0.231  0.978  0.914  1.0
[/CIF]
.