The structure described by CeSe2 crystallizes in the monoclinic Pc space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 6-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. In the second Ce site, Ce(2) is bonded to one Se(2), one Se(4), two equivalent Se(1), and two equivalent Se(3) atoms to form distorted edge-sharing CeSe6 pentagonal pyramids. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to one Ce(1) and two equivalent Ce(2) atoms. In the second Se site, Se(2) is bonded in a linear geometry to one Ce(1) and one Ce(2) atom. In the third Se site, Se(3) is bonded in a square co-planar geometry to two equivalent Ce(1) and two equivalent Ce(2) atoms. In the fourth Se site, Se(4) is bonded in a distorted trigonal non-coplanar geometry to one Ce(2) and 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   7.315
_cell_length_b   7.493
_cell_length_c   8.433
_cell_angle_alpha   58.373
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   393.601
_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  0.423  0.023  0.494  1.0
  Ce  Ce1  1  0.577  0.023  0.994  1.0
  Ce  Ce2  1  0.927  0.292  0.494  1.0
  Ce  Ce3  1  0.073  0.292  0.994  1.0
  Se  Se4  1  0.771  0.399  0.744  1.0
  Se  Se5  1  0.229  0.399  0.244  1.0
  Se  Se6  1  0.772  0.665  0.228  1.0
  Se  Se7  1  0.228  0.665  0.728  1.0
  Se  Se8  1  0.753  0.150  0.249  1.0
  Se  Se9  1  0.247  0.150  0.749  1.0
  Se  Se10  1  0.723  0.918  0.739  1.0
  Se  Se11  1  0.277  0.918  0.239  1.0
[/CIF]
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The structure described by CeSe2 crystallizes in the monoclinic Pc space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 6-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. In the second Ce site, Ce(2) is bonded to one Se(2), one Se(4), two equivalent Se(1), and two equivalent Se(3) atoms to form distorted edge-sharing CeSe6 pentagonal pyramids. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to one Ce(1) and two equivalent Ce(2) atoms. In the second Se site, Se(2) is bonded in a linear geometry to one Ce(1) and one Ce(2) atom. In the third Se site, Se(3) is bonded in a square co-planar geometry to two equivalent Ce(1) and two equivalent Ce(2) atoms. In the fourth Se site, Se(4) is bonded in a distorted trigonal non-coplanar geometry to one Ce(2) and 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   7.315
_cell_length_b   7.493
_cell_length_c   8.433
_cell_angle_alpha   58.373
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   393.601
_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  0.423  0.023  0.494  1.0
  Ce  Ce1  1  0.577  0.023  0.994  1.0
  Ce  Ce2  1  0.927  0.292  0.494  1.0
  Ce  Ce3  1  0.073  0.292  0.994  1.0
  Se  Se4  1  0.771  0.399  0.744  1.0
  Se  Se5  1  0.229  0.399  0.244  1.0
  Se  Se6  1  0.772  0.665  0.228  1.0
  Se  Se7  1  0.228  0.665  0.728  1.0
  Se  Se8  1  0.753  0.150  0.249  1.0
  Se  Se9  1  0.247  0.150  0.749  1.0
  Se  Se10  1  0.723  0.918  0.739  1.0
  Se  Se11  1  0.277  0.918  0.239  1.0
[/CIF]
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