The material structure described by CeSe2 crystallizes in the trigonal R-3c space group. Ce(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a distorted linear geometry to two equivalent Ce(1) atoms. In the second Se site, Se(1) is bonded in a distorted see-saw-like geometry to four equivalent Ce(1) atoms. is represented by the CIF card [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.637
_cell_length_b   10.637
_cell_length_c   10.637
_cell_angle_alpha   116.947
_cell_angle_beta   116.947
_cell_angle_gamma   116.947
_symmetry_Int_Tables_number   1
_cell_volume   535.249
_cell_formula_units_Z   6
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  0.071  0.429  0.250  1.0
  Ce  Ce1  1  0.429  0.250  0.071  1.0
  Ce  Ce2  1  0.250  0.071  0.429  1.0
  Ce  Ce3  1  0.571  0.750  0.929  1.0
  Ce  Ce4  1  0.750  0.929  0.571  1.0
  Ce  Ce5  1  0.929  0.571  0.750  1.0
  Se  Se6  1  0.250  0.373  0.127  1.0
  Se  Se7  1  0.373  0.127  0.250  1.0
  Se  Se8  1  0.127  0.250  0.373  1.0
  Se  Se9  1  0.750  0.627  0.873  1.0
  Se  Se10  1  0.627  0.873  0.750  1.0
  Se  Se11  1  0.873  0.750  0.627  1.0
  Se  Se12  1  0.000  0.500  0.500  1.0
  Se  Se13  1  0.500  0.500  0.000  1.0
  Se  Se14  1  0.500  0.000  0.500  1.0
  Se  Se15  1  0.500  0.000  0.000  1.0
  Se  Se16  1  0.000  0.000  0.500  1.0
  Se  Se17  1  0.000  0.500  0.000  1.0
[/CIF]
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The material structure described by CeSe2 crystallizes in the trigonal R-3c space group. Ce(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a distorted linear geometry to two equivalent Ce(1) atoms. In the second Se site, Se(1) is bonded in a distorted see-saw-like geometry to four equivalent Ce(1) atoms. is represented by the CIF card [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.637
_cell_length_b   10.637
_cell_length_c   10.637
_cell_angle_alpha   116.947
_cell_angle_beta   116.947
_cell_angle_gamma   116.947
_symmetry_Int_Tables_number   1
_cell_volume   535.249
_cell_formula_units_Z   6
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  0.071  0.429  0.250  1.0
  Ce  Ce1  1  0.429  0.250  0.071  1.0
  Ce  Ce2  1  0.250  0.071  0.429  1.0
  Ce  Ce3  1  0.571  0.750  0.929  1.0
  Ce  Ce4  1  0.750  0.929  0.571  1.0
  Ce  Ce5  1  0.929  0.571  0.750  1.0
  Se  Se6  1  0.250  0.373  0.127  1.0
  Se  Se7  1  0.373  0.127  0.250  1.0
  Se  Se8  1  0.127  0.250  0.373  1.0
  Se  Se9  1  0.750  0.627  0.873  1.0
  Se  Se10  1  0.627  0.873  0.750  1.0
  Se  Se11  1  0.873  0.750  0.627  1.0
  Se  Se12  1  0.000  0.500  0.500  1.0
  Se  Se13  1  0.500  0.500  0.000  1.0
  Se  Se14  1  0.500  0.000  0.500  1.0
  Se  Se15  1  0.500  0.000  0.000  1.0
  Se  Se16  1  0.000  0.000  0.500  1.0
  Se  Se17  1  0.000  0.500  0.000  1.0
[/CIF]
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