The material described by CeSe2 crystallizes in the monoclinic Pm space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(3), one Se(6), and two equivalent Se(4) atoms to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(3), one Se(6), and two equivalent Se(2) atoms to form corner-sharing CeSe4 tetrahedra. In the third Ce site, Ce(3) is bonded to one Se(1), one Se(5), and two equivalent Se(4) atoms to form corner-sharing CeSe4 tetrahedra. In the fourth Ce site, Ce(4) is bonded to one Se(1), one Se(5), and two equivalent Se(2) atoms to form corner-sharing CeSe4 tetrahedra. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a water-like geometry to one Ce(3) and one Ce(4) atom. In the second Se site, Se(2) is bonded in a water-like geometry to one Ce(2) and one Ce(4) atom. In the third Se site, Se(3) is bonded in a water-like geometry to one Ce(1) and one Ce(2) atom. In the fourth Se site, Se(4) is bonded in a bent 120 degrees geometry to one Ce(1) and one Ce(3) atom. In the fifth Se site, Se(5) is bonded in a bent 120 degrees geometry to one Ce(3) and one Ce(4) atom. In the sixth Se site, Se(6) 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   8.909
_cell_length_b   7.518
_cell_length_c   8.337
_cell_angle_alpha   74.213
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   537.301
_cell_formula_units_Z   4
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  0.500  0.012  0.009  1.0
  Ce  Ce1  1  0.500  0.539  0.474  1.0
  Ce  Ce2  1  0.000  0.966  0.770  1.0
  Ce  Ce3  1  0.000  0.543  0.431  1.0
  Se  Se4  1  0.000  0.335  0.755  1.0
  Se  Se5  1  0.738  0.426  0.320  1.0
  Se  Se6  1  0.262  0.426  0.320  1.0
  Se  Se7  1  0.500  0.917  0.352  1.0
  Se  Se8  1  0.256  0.822  0.938  1.0
  Se  Se9  1  0.744  0.822  0.938  1.0
  Se  Se10  1  0.000  0.895  0.465  1.0
  Se  Se11  1  0.500  0.369  0.811  1.0
[/CIF]
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The material described by CeSe2 crystallizes in the monoclinic Pm space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(3), one Se(6), and two equivalent Se(4) atoms to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(3), one Se(6), and two equivalent Se(2) atoms to form corner-sharing CeSe4 tetrahedra. In the third Ce site, Ce(3) is bonded to one Se(1), one Se(5), and two equivalent Se(4) atoms to form corner-sharing CeSe4 tetrahedra. In the fourth Ce site, Ce(4) is bonded to one Se(1), one Se(5), and two equivalent Se(2) atoms to form corner-sharing CeSe4 tetrahedra. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a water-like geometry to one Ce(3) and one Ce(4) atom. In the second Se site, Se(2) is bonded in a water-like geometry to one Ce(2) and one Ce(4) atom. In the third Se site, Se(3) is bonded in a water-like geometry to one Ce(1) and one Ce(2) atom. In the fourth Se site, Se(4) is bonded in a bent 120 degrees geometry to one Ce(1) and one Ce(3) atom. In the fifth Se site, Se(5) is bonded in a bent 120 degrees geometry to one Ce(3) and one Ce(4) atom. In the sixth Se site, Se(6) 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   8.909
_cell_length_b   7.518
_cell_length_c   8.337
_cell_angle_alpha   74.213
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   537.301
_cell_formula_units_Z   4
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  0.500  0.012  0.009  1.0
  Ce  Ce1  1  0.500  0.539  0.474  1.0
  Ce  Ce2  1  0.000  0.966  0.770  1.0
  Ce  Ce3  1  0.000  0.543  0.431  1.0
  Se  Se4  1  0.000  0.335  0.755  1.0
  Se  Se5  1  0.738  0.426  0.320  1.0
  Se  Se6  1  0.262  0.426  0.320  1.0
  Se  Se7  1  0.500  0.917  0.352  1.0
  Se  Se8  1  0.256  0.822  0.938  1.0
  Se  Se9  1  0.744  0.822  0.938  1.0
  Se  Se10  1  0.000  0.895  0.465  1.0
  Se  Se11  1  0.500  0.369  0.811  1.0
[/CIF]
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