The crystal structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the orthorhombic Cmc2_1 space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(6), one Se(7), and two equivalent Se(2) atoms to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(6), one Se(7), and two equivalent Se(1) atoms to form corner-sharing CeSe4 tetrahedra. In the third Ce site, Ce(3) is bonded to one Se(1), one Se(3), and two equivalent Se(4) atoms to form corner-sharing CeSe4 tetrahedra. In the fourth Ce site, Ce(4) is bonded to one Se(2), one Se(3), and two equivalent Se(5) atoms to form corner-sharing CeSe4 tetrahedra. There are seven inequivalent Se sites. In the first Se site, Se(3) is bonded in a bent 150 degrees geometry to one Ce(3) and one Ce(4) atom. In the second Se site, Se(4) is bonded in a bent 150 degrees geometry to two equivalent Ce(3) atoms. In the third Se site, Se(5) is bonded in a bent 150 degrees geometry to two equivalent Ce(4) atoms. In the fourth Se site, Se(6) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the fifth Se site, Se(7) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the sixth Se site, Se(1) is bonded in a bent 150 degrees geometry to one Ce(2) and one Ce(3) atom. In the seventh Se site, Se(2) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(4) atom. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.572
_cell_length_b   18.991
_cell_length_c   18.991
_cell_angle_alpha   102.828
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   3014.363
_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  0.253  0.274  0.726  1.0
  Ce  Ce1  1  0.753  0.726  0.274  1.0
  Ce  Ce2  1  0.751  0.376  0.624  1.0
  Ce  Ce3  1  0.251  0.624  0.376  1.0
  Ce  Ce4  1  0.273  0.753  0.656  1.0
  Ce  Ce5  1  0.273  0.344  0.247  1.0
  Ce  Ce6  1  0.773  0.247  0.344  1.0
  Ce  Ce7  1  0.773  0.656  0.753  1.0
  Ce  Ce8  1  0.354  0.005  0.583  1.0
  Ce  Ce9  1  0.354  0.417  0.995  1.0
  Ce  Ce10  1  0.854  0.995  0.417  1.0
  Ce  Ce11  1  0.854  0.583  0.005  1.0
  Se  Se12  1  0.803  0.333  0.479  1.0
  Se  Se13  1  0.803  0.521  0.667  1.0
  Se  Se14  1  0.303  0.667  0.521  1.0
  Se  Se15  1  0.303  0.479  0.333  1.0
  Se  Se16  1  0.293  0.128  0.683  1.0
  Se  Se17  1  0.293  0.317  0.872  1.0
  Se  Se18  1  0.793  0.872  0.317  1.0
  Se  Se19  1  0.793  0.683  0.128  1.0
  Se  Se20  1  0.836  0.108  0.350  1.0
  Se  Se21  1  0.836  0.650  0.892  1.0
  Se  Se22  1  0.336  0.892  0.650  1.0
  Se  Se23  1  0.336  0.350  0.108  1.0
  Se  Se24  1  0.478  0.252  0.292  1.0
  Se  Se25  1  0.478  0.708  0.748  1.0
  Se  Se26  1  0.978  0.748  0.708  1.0
  Se  Se27  1  0.978  0.292  0.252  1.0
  Se  Se28  1  0.147  0.988  0.471  1.0
  Se  Se29  1  0.147  0.529  0.012  1.0
  Se  Se30  1  0.647  0.012  0.529  1.0
  Se  Se31  1  0.647  0.471  0.988  1.0
  Se  Se32  1  0.955  0.306  0.694  1.0
  Se  Se33  1  0.455  0.694  0.306  1.0
  Se  Se34  1  0.452  0.345  0.655  1.0
  Se  Se35  1  0.952  0.655  0.345  1.0
[/CIF]
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The crystal structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the orthorhombic Cmc2_1 space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(6), one Se(7), and two equivalent Se(2) atoms to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(6), one Se(7), and two equivalent Se(1) atoms to form corner-sharing CeSe4 tetrahedra. In the third Ce site, Ce(3) is bonded to one Se(1), one Se(3), and two equivalent Se(4) atoms to form corner-sharing CeSe4 tetrahedra. In the fourth Ce site, Ce(4) is bonded to one Se(2), one Se(3), and two equivalent Se(5) atoms to form corner-sharing CeSe4 tetrahedra. There are seven inequivalent Se sites. In the first Se site, Se(3) is bonded in a bent 150 degrees geometry to one Ce(3) and one Ce(4) atom. In the second Se site, Se(4) is bonded in a bent 150 degrees geometry to two equivalent Ce(3) atoms. In the third Se site, Se(5) is bonded in a bent 150 degrees geometry to two equivalent Ce(4) atoms. In the fourth Se site, Se(6) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the fifth Se site, Se(7) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the sixth Se site, Se(1) is bonded in a bent 150 degrees geometry to one Ce(2) and one Ce(3) atom. In the seventh Se site, Se(2) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(4) atom. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.572
_cell_length_b   18.991
_cell_length_c   18.991
_cell_angle_alpha   102.828
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   3014.363
_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  0.253  0.274  0.726  1.0
  Ce  Ce1  1  0.753  0.726  0.274  1.0
  Ce  Ce2  1  0.751  0.376  0.624  1.0
  Ce  Ce3  1  0.251  0.624  0.376  1.0
  Ce  Ce4  1  0.273  0.753  0.656  1.0
  Ce  Ce5  1  0.273  0.344  0.247  1.0
  Ce  Ce6  1  0.773  0.247  0.344  1.0
  Ce  Ce7  1  0.773  0.656  0.753  1.0
  Ce  Ce8  1  0.354  0.005  0.583  1.0
  Ce  Ce9  1  0.354  0.417  0.995  1.0
  Ce  Ce10  1  0.854  0.995  0.417  1.0
  Ce  Ce11  1  0.854  0.583  0.005  1.0
  Se  Se12  1  0.803  0.333  0.479  1.0
  Se  Se13  1  0.803  0.521  0.667  1.0
  Se  Se14  1  0.303  0.667  0.521  1.0
  Se  Se15  1  0.303  0.479  0.333  1.0
  Se  Se16  1  0.293  0.128  0.683  1.0
  Se  Se17  1  0.293  0.317  0.872  1.0
  Se  Se18  1  0.793  0.872  0.317  1.0
  Se  Se19  1  0.793  0.683  0.128  1.0
  Se  Se20  1  0.836  0.108  0.350  1.0
  Se  Se21  1  0.836  0.650  0.892  1.0
  Se  Se22  1  0.336  0.892  0.650  1.0
  Se  Se23  1  0.336  0.350  0.108  1.0
  Se  Se24  1  0.478  0.252  0.292  1.0
  Se  Se25  1  0.478  0.708  0.748  1.0
  Se  Se26  1  0.978  0.748  0.708  1.0
  Se  Se27  1  0.978  0.292  0.252  1.0
  Se  Se28  1  0.147  0.988  0.471  1.0
  Se  Se29  1  0.147  0.529  0.012  1.0
  Se  Se30  1  0.647  0.012  0.529  1.0
  Se  Se31  1  0.647  0.471  0.988  1.0
  Se  Se32  1  0.955  0.306  0.694  1.0
  Se  Se33  1  0.455  0.694  0.306  1.0
  Se  Se34  1  0.452  0.345  0.655  1.0
  Se  Se35  1  0.952  0.655  0.345  1.0
[/CIF]
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