The structure described by CeSe2 crystallizes in the tetragonal P4/nnc space group. Ce(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form distorted corner-sharing CeSe4 trigonal pyramids. There are four inequivalent Se sites. In the first Se site, Se(3) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the second Se site, Se(4) is bonded in a bent 120 degrees geometry to two equivalent Ce(1) atoms. In the third Se site, Se(1) is bonded in a water-like geometry to two equivalent Ce(1) atoms. In the fourth Se site, Se(2) is bonded in a bent 120 degrees geometry to two equivalent Ce(1) atoms. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.516
_cell_length_b   17.629
_cell_length_c   17.629
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   2335.802
_cell_formula_units_Z   16
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  0.724  0.711  0.402  1.0
  Ce  Ce1  1  0.724  0.289  0.598  1.0
  Ce  Ce2  1  0.776  0.211  0.902  1.0
  Ce  Ce3  1  0.776  0.789  0.098  1.0
  Ce  Ce4  1  0.276  0.711  0.598  1.0
  Ce  Ce5  1  0.276  0.289  0.402  1.0
  Ce  Ce6  1  0.224  0.211  0.098  1.0
  Ce  Ce7  1  0.224  0.789  0.902  1.0
  Ce  Ce8  1  0.724  0.402  0.289  1.0
  Ce  Ce9  1  0.724  0.598  0.711  1.0
  Ce  Ce10  1  0.776  0.902  0.789  1.0
  Ce  Ce11  1  0.776  0.098  0.211  1.0
  Ce  Ce12  1  0.276  0.598  0.289  1.0
  Ce  Ce13  1  0.276  0.402  0.711  1.0
  Ce  Ce14  1  0.224  0.098  0.789  1.0
  Ce  Ce15  1  0.224  0.902  0.211  1.0
  Se  Se16  1  0.500  0.593  0.407  1.0
  Se  Se17  1  0.500  0.407  0.593  1.0
  Se  Se18  1  0.000  0.093  0.907  1.0
  Se  Se19  1  0.000  0.907  0.093  1.0
  Se  Se20  1  0.500  0.593  0.593  1.0
  Se  Se21  1  0.500  0.407  0.407  1.0
  Se  Se22  1  0.000  0.093  0.093  1.0
  Se  Se23  1  0.000  0.907  0.907  1.0
  Se  Se24  1  0.000  0.608  0.392  1.0
  Se  Se25  1  0.000  0.392  0.608  1.0
  Se  Se26  1  0.500  0.108  0.892  1.0
  Se  Se27  1  0.500  0.892  0.108  1.0
  Se  Se28  1  0.000  0.608  0.608  1.0
  Se  Se29  1  0.000  0.392  0.392  1.0
  Se  Se30  1  0.500  0.108  0.108  1.0
  Se  Se31  1  0.500  0.892  0.892  1.0
  Se  Se32  1  0.750  0.750  0.250  1.0
  Se  Se33  1  0.750  0.250  0.750  1.0
  Se  Se34  1  0.250  0.750  0.750  1.0
  Se  Se35  1  0.250  0.250  0.250  1.0
  Se  Se36  1  0.750  0.250  0.250  1.0
  Se  Se37  1  0.750  0.750  0.750  1.0
  Se  Se38  1  0.250  0.750  0.250  1.0
  Se  Se39  1  0.250  0.250  0.750  1.0
  Se  Se40  1  0.500  0.792  0.500  1.0
  Se  Se41  1  0.500  0.208  0.500  1.0
  Se  Se42  1  0.000  0.292  0.000  1.0
  Se  Se43  1  0.000  0.708  0.000  1.0
  Se  Se44  1  0.500  0.500  0.208  1.0
  Se  Se45  1  0.500  0.500  0.792  1.0
  Se  Se46  1  0.000  0.000  0.708  1.0
  Se  Se47  1  0.000  0.000  0.292  1.0
[/CIF]
.
The structure described by CeSe2 crystallizes in the tetragonal P4/nnc space group. Ce(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form distorted corner-sharing CeSe4 trigonal pyramids. There are four inequivalent Se sites. In the first Se site, Se(3) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the second Se site, Se(4) is bonded in a bent 120 degrees geometry to two equivalent Ce(1) atoms. In the third Se site, Se(1) is bonded in a water-like geometry to two equivalent Ce(1) atoms. In the fourth Se site, Se(2) is bonded in a bent 120 degrees geometry to two equivalent Ce(1) atoms. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.516
_cell_length_b   17.629
_cell_length_c   17.629
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   2335.802
_cell_formula_units_Z   16
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  0.724  0.711  0.402  1.0
  Ce  Ce1  1  0.724  0.289  0.598  1.0
  Ce  Ce2  1  0.776  0.211  0.902  1.0
  Ce  Ce3  1  0.776  0.789  0.098  1.0
  Ce  Ce4  1  0.276  0.711  0.598  1.0
  Ce  Ce5  1  0.276  0.289  0.402  1.0
  Ce  Ce6  1  0.224  0.211  0.098  1.0
  Ce  Ce7  1  0.224  0.789  0.902  1.0
  Ce  Ce8  1  0.724  0.402  0.289  1.0
  Ce  Ce9  1  0.724  0.598  0.711  1.0
  Ce  Ce10  1  0.776  0.902  0.789  1.0
  Ce  Ce11  1  0.776  0.098  0.211  1.0
  Ce  Ce12  1  0.276  0.598  0.289  1.0
  Ce  Ce13  1  0.276  0.402  0.711  1.0
  Ce  Ce14  1  0.224  0.098  0.789  1.0
  Ce  Ce15  1  0.224  0.902  0.211  1.0
  Se  Se16  1  0.500  0.593  0.407  1.0
  Se  Se17  1  0.500  0.407  0.593  1.0
  Se  Se18  1  0.000  0.093  0.907  1.0
  Se  Se19  1  0.000  0.907  0.093  1.0
  Se  Se20  1  0.500  0.593  0.593  1.0
  Se  Se21  1  0.500  0.407  0.407  1.0
  Se  Se22  1  0.000  0.093  0.093  1.0
  Se  Se23  1  0.000  0.907  0.907  1.0
  Se  Se24  1  0.000  0.608  0.392  1.0
  Se  Se25  1  0.000  0.392  0.608  1.0
  Se  Se26  1  0.500  0.108  0.892  1.0
  Se  Se27  1  0.500  0.892  0.108  1.0
  Se  Se28  1  0.000  0.608  0.608  1.0
  Se  Se29  1  0.000  0.392  0.392  1.0
  Se  Se30  1  0.500  0.108  0.108  1.0
  Se  Se31  1  0.500  0.892  0.892  1.0
  Se  Se32  1  0.750  0.750  0.250  1.0
  Se  Se33  1  0.750  0.250  0.750  1.0
  Se  Se34  1  0.250  0.750  0.750  1.0
  Se  Se35  1  0.250  0.250  0.250  1.0
  Se  Se36  1  0.750  0.250  0.250  1.0
  Se  Se37  1  0.750  0.750  0.750  1.0
  Se  Se38  1  0.250  0.750  0.250  1.0
  Se  Se39  1  0.250  0.250  0.750  1.0
  Se  Se40  1  0.500  0.792  0.500  1.0
  Se  Se41  1  0.500  0.208  0.500  1.0
  Se  Se42  1  0.000  0.292  0.000  1.0
  Se  Se43  1  0.000  0.708  0.000  1.0
  Se  Se44  1  0.500  0.500  0.208  1.0
  Se  Se45  1  0.500  0.500  0.792  1.0
  Se  Se46  1  0.000  0.000  0.708  1.0
  Se  Se47  1  0.000  0.000  0.292  1.0
[/CIF]
.