The material structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the monoclinic C2/c space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(1), one Se(3), one Se(4), and one Se(5) atom to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(2), one Se(3), one Se(4), and one Se(5) atom to form corner-sharing CeSe4 tetrahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a linear 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(2) atoms. In the third Se site, Se(3) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the fourth Se site, Se(4) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the fifth Se site, Se(5) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.116
_cell_length_b   12.116
_cell_length_c   12.100
_cell_angle_alpha   104.456
_cell_angle_beta   104.456
_cell_angle_gamma   119.793
_symmetry_Int_Tables_number   1
_cell_volume   1336.930
_cell_formula_units_Z   8
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  0.033  0.251  0.573  1.0
  Ce  Ce1  1  0.749  0.967  0.927  1.0
  Ce  Ce2  1  0.967  0.749  0.427  1.0
  Ce  Ce3  1  0.251  0.033  0.073  1.0
  Ce  Ce4  1  0.348  0.664  0.039  1.0
  Ce  Ce5  1  0.336  0.652  0.461  1.0
  Ce  Ce6  1  0.652  0.336  0.961  1.0
  Ce  Ce7  1  0.664  0.348  0.539  1.0
  Se  Se8  1  0.000  0.000  0.500  1.0
  Se  Se9  1  0.000  0.000  0.000  1.0
  Se  Se10  1  0.383  0.617  0.250  1.0
  Se  Se11  1  0.617  0.383  0.750  1.0
  Se  Se12  1  0.143  0.394  0.443  1.0
  Se  Se13  1  0.606  0.857  0.057  1.0
  Se  Se14  1  0.857  0.606  0.557  1.0
  Se  Se15  1  0.394  0.143  0.943  1.0
  Se  Se16  1  0.205  0.412  0.829  1.0
  Se  Se17  1  0.588  0.795  0.671  1.0
  Se  Se18  1  0.795  0.588  0.171  1.0
  Se  Se19  1  0.412  0.205  0.329  1.0
  Se  Se20  1  0.799  0.223  0.972  1.0
  Se  Se21  1  0.777  0.201  0.528  1.0
  Se  Se22  1  0.201  0.777  0.028  1.0
  Se  Se23  1  0.223  0.799  0.472  1.0
[/CIF]
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The material structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the monoclinic C2/c space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(1), one Se(3), one Se(4), and one Se(5) atom to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(2), one Se(3), one Se(4), and one Se(5) atom to form corner-sharing CeSe4 tetrahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a linear 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(2) atoms. In the third Se site, Se(3) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the fourth Se site, Se(4) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the fifth Se site, Se(5) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.116
_cell_length_b   12.116
_cell_length_c   12.100
_cell_angle_alpha   104.456
_cell_angle_beta   104.456
_cell_angle_gamma   119.793
_symmetry_Int_Tables_number   1
_cell_volume   1336.930
_cell_formula_units_Z   8
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  0.033  0.251  0.573  1.0
  Ce  Ce1  1  0.749  0.967  0.927  1.0
  Ce  Ce2  1  0.967  0.749  0.427  1.0
  Ce  Ce3  1  0.251  0.033  0.073  1.0
  Ce  Ce4  1  0.348  0.664  0.039  1.0
  Ce  Ce5  1  0.336  0.652  0.461  1.0
  Ce  Ce6  1  0.652  0.336  0.961  1.0
  Ce  Ce7  1  0.664  0.348  0.539  1.0
  Se  Se8  1  0.000  0.000  0.500  1.0
  Se  Se9  1  0.000  0.000  0.000  1.0
  Se  Se10  1  0.383  0.617  0.250  1.0
  Se  Se11  1  0.617  0.383  0.750  1.0
  Se  Se12  1  0.143  0.394  0.443  1.0
  Se  Se13  1  0.606  0.857  0.057  1.0
  Se  Se14  1  0.857  0.606  0.557  1.0
  Se  Se15  1  0.394  0.143  0.943  1.0
  Se  Se16  1  0.205  0.412  0.829  1.0
  Se  Se17  1  0.588  0.795  0.671  1.0
  Se  Se18  1  0.795  0.588  0.171  1.0
  Se  Se19  1  0.412  0.205  0.329  1.0
  Se  Se20  1  0.799  0.223  0.972  1.0
  Se  Se21  1  0.777  0.201  0.528  1.0
  Se  Se22  1  0.201  0.777  0.028  1.0
  Se  Se23  1  0.223  0.799  0.472  1.0
[/CIF]
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