The crystal structure described by Ce2HfSe5 crystallizes in the orthorhombic Pnma space group. Ce(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. Hf(1) is bonded to one Se(1), one Se(2), one Se(3), and four equivalent Se(4) atoms to form distorted edge-sharing HfSe7 pentagonal bipyramids. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to four equivalent Ce(1) and one Hf(1) atom to form a mixture of distorted edge, face, and corner-sharing SeCe4Hf trigonal bipyramids. In the second Se site, Se(2) is bonded to four equivalent Ce(1) and one Hf(1) atom to form a mixture of edge, face, and corner-sharing SeCe4Hf square pyramids. In the third Se site, Se(3) is bonded to four equivalent Ce(1) and one Hf(1) atom to form a mixture of distorted edge and corner-sharing SeCe4Hf trigonal bipyramids. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to two equivalent Ce(1) and two equivalent Hf(1) atoms. is represented by the CIF file [CIF]
data_Ce2HfSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.734
_cell_length_b   8.418
_cell_length_c   12.068
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   785.754
_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
  Ce  Ce0  1  0.545  0.501  0.674  1.0
  Ce  Ce1  1  0.045  0.499  0.826  1.0
  Ce  Ce2  1  0.955  0.999  0.174  1.0
  Ce  Ce3  1  0.455  0.001  0.326  1.0
  Ce  Ce4  1  0.455  0.499  0.326  1.0
  Ce  Ce5  1  0.955  0.501  0.174  1.0
  Ce  Ce6  1  0.045  0.001  0.826  1.0
  Ce  Ce7  1  0.545  0.999  0.674  1.0
  Hf  Hf8  1  0.074  0.250  0.508  1.0
  Hf  Hf9  1  0.574  0.750  0.992  1.0
  Hf  Hf10  1  0.426  0.250  0.008  1.0
  Hf  Hf11  1  0.926  0.750  0.492  1.0
  Se  Se12  1  0.331  0.250  0.794  1.0
  Se  Se13  1  0.831  0.750  0.706  1.0
  Se  Se14  1  0.169  0.250  0.294  1.0
  Se  Se15  1  0.669  0.750  0.206  1.0
  Se  Se16  1  0.057  0.250  0.006  1.0
  Se  Se17  1  0.557  0.750  0.494  1.0
  Se  Se18  1  0.443  0.250  0.506  1.0
  Se  Se19  1  0.943  0.750  0.994  1.0
  Se  Se20  1  0.853  0.250  0.687  1.0
  Se  Se21  1  0.353  0.750  0.813  1.0
  Se  Se22  1  0.647  0.250  0.187  1.0
  Se  Se23  1  0.147  0.750  0.313  1.0
  Se  Se24  1  0.672  0.464  0.921  1.0
  Se  Se25  1  0.172  0.536  0.579  1.0
  Se  Se26  1  0.828  0.036  0.421  1.0
  Se  Se27  1  0.328  0.964  0.079  1.0
  Se  Se28  1  0.328  0.536  0.079  1.0
  Se  Se29  1  0.828  0.464  0.421  1.0
  Se  Se30  1  0.172  0.964  0.579  1.0
  Se  Se31  1  0.672  0.036  0.921  1.0
[/CIF]
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The crystal structure described by Ce2HfSe5 crystallizes in the orthorhombic Pnma space group. Ce(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. Hf(1) is bonded to one Se(1), one Se(2), one Se(3), and four equivalent Se(4) atoms to form distorted edge-sharing HfSe7 pentagonal bipyramids. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to four equivalent Ce(1) and one Hf(1) atom to form a mixture of distorted edge, face, and corner-sharing SeCe4Hf trigonal bipyramids. In the second Se site, Se(2) is bonded to four equivalent Ce(1) and one Hf(1) atom to form a mixture of edge, face, and corner-sharing SeCe4Hf square pyramids. In the third Se site, Se(3) is bonded to four equivalent Ce(1) and one Hf(1) atom to form a mixture of distorted edge and corner-sharing SeCe4Hf trigonal bipyramids. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to two equivalent Ce(1) and two equivalent Hf(1) atoms. is represented by the CIF file [CIF]
data_Ce2HfSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.734
_cell_length_b   8.418
_cell_length_c   12.068
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   785.754
_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
  Ce  Ce0  1  0.545  0.501  0.674  1.0
  Ce  Ce1  1  0.045  0.499  0.826  1.0
  Ce  Ce2  1  0.955  0.999  0.174  1.0
  Ce  Ce3  1  0.455  0.001  0.326  1.0
  Ce  Ce4  1  0.455  0.499  0.326  1.0
  Ce  Ce5  1  0.955  0.501  0.174  1.0
  Ce  Ce6  1  0.045  0.001  0.826  1.0
  Ce  Ce7  1  0.545  0.999  0.674  1.0
  Hf  Hf8  1  0.074  0.250  0.508  1.0
  Hf  Hf9  1  0.574  0.750  0.992  1.0
  Hf  Hf10  1  0.426  0.250  0.008  1.0
  Hf  Hf11  1  0.926  0.750  0.492  1.0
  Se  Se12  1  0.331  0.250  0.794  1.0
  Se  Se13  1  0.831  0.750  0.706  1.0
  Se  Se14  1  0.169  0.250  0.294  1.0
  Se  Se15  1  0.669  0.750  0.206  1.0
  Se  Se16  1  0.057  0.250  0.006  1.0
  Se  Se17  1  0.557  0.750  0.494  1.0
  Se  Se18  1  0.443  0.250  0.506  1.0
  Se  Se19  1  0.943  0.750  0.994  1.0
  Se  Se20  1  0.853  0.250  0.687  1.0
  Se  Se21  1  0.353  0.750  0.813  1.0
  Se  Se22  1  0.647  0.250  0.187  1.0
  Se  Se23  1  0.147  0.750  0.313  1.0
  Se  Se24  1  0.672  0.464  0.921  1.0
  Se  Se25  1  0.172  0.536  0.579  1.0
  Se  Se26  1  0.828  0.036  0.421  1.0
  Se  Se27  1  0.328  0.964  0.079  1.0
  Se  Se28  1  0.328  0.536  0.079  1.0
  Se  Se29  1  0.828  0.464  0.421  1.0
  Se  Se30  1  0.172  0.964  0.579  1.0
  Se  Se31  1  0.672  0.036  0.921  1.0
[/CIF]
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