The crystal structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the trigonal R-3m 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 bent 150 degrees 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 bent 150 degrees 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 CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   15.689
_cell_length_b   15.689
_cell_length_c   15.689
_cell_angle_alpha   94.241
_cell_angle_beta   94.241
_cell_angle_gamma   94.241
_symmetry_Int_Tables_number   1
_cell_volume   3828.747
_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  0.124  0.668  0.896  1.0
  Ce  Ce1  1  0.668  0.896  0.124  1.0
  Ce  Ce2  1  0.896  0.124  0.668  1.0
  Ce  Ce3  1  0.124  0.896  0.668  1.0
  Ce  Ce4  1  0.896  0.668  0.124  1.0
  Ce  Ce5  1  0.668  0.124  0.896  1.0
  Ce  Ce6  1  0.876  0.332  0.104  1.0
  Ce  Ce7  1  0.332  0.104  0.876  1.0
  Ce  Ce8  1  0.104  0.876  0.332  1.0
  Ce  Ce9  1  0.876  0.104  0.332  1.0
  Ce  Ce10  1  0.104  0.332  0.876  1.0
  Ce  Ce11  1  0.332  0.876  0.104  1.0
  Se  Se12  1  0.110  0.751  0.751  1.0
  Se  Se13  1  0.751  0.751  0.110  1.0
  Se  Se14  1  0.751  0.110  0.751  1.0
  Se  Se15  1  0.890  0.249  0.249  1.0
  Se  Se16  1  0.249  0.249  0.890  1.0
  Se  Se17  1  0.249  0.890  0.249  1.0
  Se  Se18  1  0.146  0.500  0.854  1.0
  Se  Se19  1  0.500  0.854  0.146  1.0
  Se  Se20  1  0.854  0.146  0.500  1.0
  Se  Se21  1  0.146  0.854  0.500  1.0
  Se  Se22  1  0.854  0.500  0.146  1.0
  Se  Se23  1  0.500  0.146  0.854  1.0
  Se  Se24  1  0.978  0.681  0.978  1.0
  Se  Se25  1  0.681  0.978  0.978  1.0
  Se  Se26  1  0.978  0.978  0.681  1.0
  Se  Se27  1  0.022  0.319  0.022  1.0
  Se  Se28  1  0.319  0.022  0.022  1.0
  Se  Se29  1  0.022  0.022  0.319  1.0
  Se  Se30  1  0.263  0.737  0.000  1.0
  Se  Se31  1  0.737  0.000  0.263  1.0
  Se  Se32  1  0.000  0.263  0.737  1.0
  Se  Se33  1  0.263  0.000  0.737  1.0
  Se  Se34  1  0.000  0.737  0.263  1.0
  Se  Se35  1  0.737  0.263  0.000  1.0
[/CIF]
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The crystal structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the trigonal R-3m 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 bent 150 degrees 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 bent 150 degrees 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 CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   15.689
_cell_length_b   15.689
_cell_length_c   15.689
_cell_angle_alpha   94.241
_cell_angle_beta   94.241
_cell_angle_gamma   94.241
_symmetry_Int_Tables_number   1
_cell_volume   3828.747
_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  0.124  0.668  0.896  1.0
  Ce  Ce1  1  0.668  0.896  0.124  1.0
  Ce  Ce2  1  0.896  0.124  0.668  1.0
  Ce  Ce3  1  0.124  0.896  0.668  1.0
  Ce  Ce4  1  0.896  0.668  0.124  1.0
  Ce  Ce5  1  0.668  0.124  0.896  1.0
  Ce  Ce6  1  0.876  0.332  0.104  1.0
  Ce  Ce7  1  0.332  0.104  0.876  1.0
  Ce  Ce8  1  0.104  0.876  0.332  1.0
  Ce  Ce9  1  0.876  0.104  0.332  1.0
  Ce  Ce10  1  0.104  0.332  0.876  1.0
  Ce  Ce11  1  0.332  0.876  0.104  1.0
  Se  Se12  1  0.110  0.751  0.751  1.0
  Se  Se13  1  0.751  0.751  0.110  1.0
  Se  Se14  1  0.751  0.110  0.751  1.0
  Se  Se15  1  0.890  0.249  0.249  1.0
  Se  Se16  1  0.249  0.249  0.890  1.0
  Se  Se17  1  0.249  0.890  0.249  1.0
  Se  Se18  1  0.146  0.500  0.854  1.0
  Se  Se19  1  0.500  0.854  0.146  1.0
  Se  Se20  1  0.854  0.146  0.500  1.0
  Se  Se21  1  0.146  0.854  0.500  1.0
  Se  Se22  1  0.854  0.500  0.146  1.0
  Se  Se23  1  0.500  0.146  0.854  1.0
  Se  Se24  1  0.978  0.681  0.978  1.0
  Se  Se25  1  0.681  0.978  0.978  1.0
  Se  Se26  1  0.978  0.978  0.681  1.0
  Se  Se27  1  0.022  0.319  0.022  1.0
  Se  Se28  1  0.319  0.022  0.022  1.0
  Se  Se29  1  0.022  0.022  0.319  1.0
  Se  Se30  1  0.263  0.737  0.000  1.0
  Se  Se31  1  0.737  0.000  0.263  1.0
  Se  Se32  1  0.000  0.263  0.737  1.0
  Se  Se33  1  0.263  0.000  0.737  1.0
  Se  Se34  1  0.000  0.737  0.263  1.0
  Se  Se35  1  0.737  0.263  0.000  1.0
[/CIF]
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