The material described by CeSe2 crystallizes in the trigonal P-31m space group. Ce(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form corner-sharing CeSe4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a water-like geometry to two equivalent Ce(1) atoms. In the second Se site, Se(2) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. In the third Se site, Se(3) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the fourth Se site, Se(4) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.604
_cell_length_b   18.849
_cell_length_c   18.849
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   2339.389
_cell_formula_units_Z   12
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  0.220  0.533  0.845  1.0
  Ce  Ce1  1  0.220  0.155  0.689  1.0
  Ce  Ce2  1  0.220  0.311  0.467  1.0
  Ce  Ce3  1  0.220  0.467  0.311  1.0
  Ce  Ce4  1  0.220  0.689  0.155  1.0
  Ce  Ce5  1  0.220  0.845  0.533  1.0
  Ce  Ce6  1  0.780  0.467  0.155  1.0
  Ce  Ce7  1  0.780  0.845  0.311  1.0
  Ce  Ce8  1  0.780  0.689  0.533  1.0
  Ce  Ce9  1  0.780  0.533  0.689  1.0
  Ce  Ce10  1  0.780  0.311  0.845  1.0
  Ce  Ce11  1  0.780  0.155  0.467  1.0
  Se  Se12  1  0.000  0.186  0.814  1.0
  Se  Se13  1  0.000  0.186  0.373  1.0
  Se  Se14  1  0.000  0.627  0.814  1.0
  Se  Se15  1  0.000  0.814  0.627  1.0
  Se  Se16  1  0.000  0.373  0.186  1.0
  Se  Se17  1  0.000  0.814  0.186  1.0
  Se  Se18  1  0.653  0.385  0.000  1.0
  Se  Se19  1  0.653  0.000  0.385  1.0
  Se  Se20  1  0.653  0.615  0.615  1.0
  Se  Se21  1  0.347  0.615  0.000  1.0
  Se  Se22  1  0.347  0.000  0.615  1.0
  Se  Se23  1  0.347  0.385  0.385  1.0
  Se  Se24  1  0.000  0.411  0.822  1.0
  Se  Se25  1  0.000  0.178  0.589  1.0
  Se  Se26  1  0.000  0.411  0.589  1.0
  Se  Se27  1  0.000  0.589  0.411  1.0
  Se  Se28  1  0.000  0.589  0.178  1.0
  Se  Se29  1  0.000  0.822  0.411  1.0
  Se  Se30  1  0.500  0.258  0.742  1.0
  Se  Se31  1  0.500  0.258  0.515  1.0
  Se  Se32  1  0.500  0.485  0.742  1.0
  Se  Se33  1  0.500  0.742  0.485  1.0
  Se  Se34  1  0.500  0.515  0.258  1.0
  Se  Se35  1  0.500  0.742  0.258  1.0
[/CIF]
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The material described by CeSe2 crystallizes in the trigonal P-31m space group. Ce(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form corner-sharing CeSe4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a water-like geometry to two equivalent Ce(1) atoms. In the second Se site, Se(2) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. In the third Se site, Se(3) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the fourth Se site, Se(4) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.604
_cell_length_b   18.849
_cell_length_c   18.849
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   2339.389
_cell_formula_units_Z   12
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  0.220  0.533  0.845  1.0
  Ce  Ce1  1  0.220  0.155  0.689  1.0
  Ce  Ce2  1  0.220  0.311  0.467  1.0
  Ce  Ce3  1  0.220  0.467  0.311  1.0
  Ce  Ce4  1  0.220  0.689  0.155  1.0
  Ce  Ce5  1  0.220  0.845  0.533  1.0
  Ce  Ce6  1  0.780  0.467  0.155  1.0
  Ce  Ce7  1  0.780  0.845  0.311  1.0
  Ce  Ce8  1  0.780  0.689  0.533  1.0
  Ce  Ce9  1  0.780  0.533  0.689  1.0
  Ce  Ce10  1  0.780  0.311  0.845  1.0
  Ce  Ce11  1  0.780  0.155  0.467  1.0
  Se  Se12  1  0.000  0.186  0.814  1.0
  Se  Se13  1  0.000  0.186  0.373  1.0
  Se  Se14  1  0.000  0.627  0.814  1.0
  Se  Se15  1  0.000  0.814  0.627  1.0
  Se  Se16  1  0.000  0.373  0.186  1.0
  Se  Se17  1  0.000  0.814  0.186  1.0
  Se  Se18  1  0.653  0.385  0.000  1.0
  Se  Se19  1  0.653  0.000  0.385  1.0
  Se  Se20  1  0.653  0.615  0.615  1.0
  Se  Se21  1  0.347  0.615  0.000  1.0
  Se  Se22  1  0.347  0.000  0.615  1.0
  Se  Se23  1  0.347  0.385  0.385  1.0
  Se  Se24  1  0.000  0.411  0.822  1.0
  Se  Se25  1  0.000  0.178  0.589  1.0
  Se  Se26  1  0.000  0.411  0.589  1.0
  Se  Se27  1  0.000  0.589  0.411  1.0
  Se  Se28  1  0.000  0.589  0.178  1.0
  Se  Se29  1  0.000  0.822  0.411  1.0
  Se  Se30  1  0.500  0.258  0.742  1.0
  Se  Se31  1  0.500  0.258  0.515  1.0
  Se  Se32  1  0.500  0.485  0.742  1.0
  Se  Se33  1  0.500  0.742  0.485  1.0
  Se  Se34  1  0.500  0.515  0.258  1.0
  Se  Se35  1  0.500  0.742  0.258  1.0
[/CIF]
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