The material described by CeSe2 crystallizes in the trigonal R-3c space group. Ce(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form corner-sharing CeSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(2) is bonded in a bent 120 degrees geometry to two equivalent Ce(1) atoms. In the second Se site, Se(3) 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 linear 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   12.527
_cell_length_b   12.527
_cell_length_c   18.498
_cell_angle_alpha   70.208
_cell_angle_beta   70.208
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   2313.824
_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  0.374  0.029  0.649  1.0
  Ce  Ce1  1  0.029  0.947  0.649  1.0
  Ce  Ce2  1  0.947  0.374  0.649  1.0
  Ce  Ce3  1  0.529  0.874  0.149  1.0
  Ce  Ce4  1  0.874  0.447  0.149  1.0
  Ce  Ce5  1  0.447  0.529  0.149  1.0
  Ce  Ce6  1  0.626  0.971  0.351  1.0
  Ce  Ce7  1  0.971  0.053  0.351  1.0
  Ce  Ce8  1  0.053  0.626  0.351  1.0
  Ce  Ce9  1  0.471  0.126  0.851  1.0
  Ce  Ce10  1  0.126  0.553  0.851  1.0
  Ce  Ce11  1  0.553  0.471  0.851  1.0
  Se  Se12  1  0.500  0.000  0.500  1.0
  Se  Se13  1  0.000  0.000  0.500  1.0
  Se  Se14  1  0.000  0.500  0.500  1.0
  Se  Se15  1  0.500  1.000  1.000  1.0
  Se  Se16  1  1.000  0.500  1.000  1.0
  Se  Se17  1  0.500  0.500  1.000  1.0
  Se  Se18  1  0.750  0.522  0.750  1.0
  Se  Se19  1  0.522  0.979  0.750  1.0
  Se  Se20  1  0.979  0.750  0.750  1.0
  Se  Se21  1  0.022  0.250  0.250  1.0
  Se  Se22  1  0.250  0.479  0.250  1.0
  Se  Se23  1  0.479  0.022  0.250  1.0
  Se  Se24  1  0.260  0.882  0.671  1.0
  Se  Se25  1  0.882  0.187  0.671  1.0
  Se  Se26  1  0.187  0.260  0.671  1.0
  Se  Se27  1  0.382  0.760  0.171  1.0
  Se  Se28  1  0.760  0.687  0.171  1.0
  Se  Se29  1  0.687  0.382  0.171  1.0
  Se  Se30  1  0.740  0.118  0.329  1.0
  Se  Se31  1  0.118  0.813  0.329  1.0
  Se  Se32  1  0.813  0.740  0.329  1.0
  Se  Se33  1  0.618  0.240  0.829  1.0
  Se  Se34  1  0.240  0.313  0.829  1.0
  Se  Se35  1  0.313  0.618  0.829  1.0
[/CIF]
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The material described by CeSe2 crystallizes in the trigonal R-3c space group. Ce(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form corner-sharing CeSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(2) is bonded in a bent 120 degrees geometry to two equivalent Ce(1) atoms. In the second Se site, Se(3) 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 linear 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   12.527
_cell_length_b   12.527
_cell_length_c   18.498
_cell_angle_alpha   70.208
_cell_angle_beta   70.208
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   2313.824
_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  0.374  0.029  0.649  1.0
  Ce  Ce1  1  0.029  0.947  0.649  1.0
  Ce  Ce2  1  0.947  0.374  0.649  1.0
  Ce  Ce3  1  0.529  0.874  0.149  1.0
  Ce  Ce4  1  0.874  0.447  0.149  1.0
  Ce  Ce5  1  0.447  0.529  0.149  1.0
  Ce  Ce6  1  0.626  0.971  0.351  1.0
  Ce  Ce7  1  0.971  0.053  0.351  1.0
  Ce  Ce8  1  0.053  0.626  0.351  1.0
  Ce  Ce9  1  0.471  0.126  0.851  1.0
  Ce  Ce10  1  0.126  0.553  0.851  1.0
  Ce  Ce11  1  0.553  0.471  0.851  1.0
  Se  Se12  1  0.500  0.000  0.500  1.0
  Se  Se13  1  0.000  0.000  0.500  1.0
  Se  Se14  1  0.000  0.500  0.500  1.0
  Se  Se15  1  0.500  1.000  1.000  1.0
  Se  Se16  1  1.000  0.500  1.000  1.0
  Se  Se17  1  0.500  0.500  1.000  1.0
  Se  Se18  1  0.750  0.522  0.750  1.0
  Se  Se19  1  0.522  0.979  0.750  1.0
  Se  Se20  1  0.979  0.750  0.750  1.0
  Se  Se21  1  0.022  0.250  0.250  1.0
  Se  Se22  1  0.250  0.479  0.250  1.0
  Se  Se23  1  0.479  0.022  0.250  1.0
  Se  Se24  1  0.260  0.882  0.671  1.0
  Se  Se25  1  0.882  0.187  0.671  1.0
  Se  Se26  1  0.187  0.260  0.671  1.0
  Se  Se27  1  0.382  0.760  0.171  1.0
  Se  Se28  1  0.760  0.687  0.171  1.0
  Se  Se29  1  0.687  0.382  0.171  1.0
  Se  Se30  1  0.740  0.118  0.329  1.0
  Se  Se31  1  0.118  0.813  0.329  1.0
  Se  Se32  1  0.813  0.740  0.329  1.0
  Se  Se33  1  0.618  0.240  0.829  1.0
  Se  Se34  1  0.240  0.313  0.829  1.0
  Se  Se35  1  0.313  0.618  0.829  1.0
[/CIF]
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