The material structure described by CeSe2 crystallizes in the orthorhombic Pmc2_1 space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), two equivalent Se(2), two equivalent Se(5), and two equivalent Se(6) atoms. In the second Ce site, Ce(2) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(5), and two equivalent Se(6) atoms. In the third Ce site, Ce(3) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), two equivalent Se(4), two equivalent Se(5), and two equivalent Se(6) atoms. In the fourth Ce site, Ce(4) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(5), and two equivalent Se(6) atoms. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ce(3), one Ce(4), and two equivalent Ce(2) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the second Se site, Se(2) is bonded to one Ce(3), one Ce(4), and two equivalent Ce(1) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the third Se site, Se(3) is bonded to one Ce(1), one Ce(2), and two equivalent Ce(4) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the fourth Se site, Se(4) is bonded to one Ce(1), one Ce(2), and two equivalent Ce(3) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one Ce(1), one Ce(2), one Ce(3), one Ce(4), and two equivalent Se(5) atoms. In the sixth Se site, Se(6) is bonded in a 6-coordinate geometry to one Ce(1), one Ce(2), one Ce(3), one Ce(4), and two equivalent Se(6) atoms. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.884
_cell_length_b   5.641
_cell_length_c   16.472
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   639.626
_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  0.001  0.500  0.460  1.0
  Ce  Ce1  1  0.999  0.500  0.960  1.0
  Ce  Ce2  1  0.491  0.500  0.200  1.0
  Ce  Ce3  1  0.509  0.500  0.700  1.0
  Ce  Ce4  1  0.004  0.000  0.765  1.0
  Ce  Ce5  1  0.996  0.000  0.265  1.0
  Ce  Ce6  1  0.472  0.000  0.007  1.0
  Ce  Ce7  1  0.528  0.000  0.507  1.0
  Se  Se8  1  0.618  0.000  0.173  1.0
  Se  Se9  1  0.382  0.000  0.673  1.0
  Se  Se10  1  0.139  0.000  0.435  1.0
  Se  Se11  1  0.861  0.000  0.935  1.0
  Se  Se12  1  0.605  0.500  0.029  1.0
  Se  Se13  1  0.395  0.500  0.529  1.0
  Se  Se14  1  0.133  0.500  0.294  1.0
  Se  Se15  1  0.867  0.500  0.794  1.0
  Se  Se16  1  0.679  0.746  0.361  1.0
  Se  Se17  1  0.679  0.254  0.361  1.0
  Se  Se18  1  0.321  0.254  0.861  1.0
  Se  Se19  1  0.321  0.746  0.861  1.0
  Se  Se20  1  0.156  0.753  0.106  1.0
  Se  Se21  1  0.156  0.247  0.106  1.0
  Se  Se22  1  0.844  0.247  0.606  1.0
  Se  Se23  1  0.844  0.753  0.606  1.0
[/CIF]
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The material structure described by CeSe2 crystallizes in the orthorhombic Pmc2_1 space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), two equivalent Se(2), two equivalent Se(5), and two equivalent Se(6) atoms. In the second Ce site, Ce(2) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(5), and two equivalent Se(6) atoms. In the third Ce site, Ce(3) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), two equivalent Se(4), two equivalent Se(5), and two equivalent Se(6) atoms. In the fourth Ce site, Ce(4) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(5), and two equivalent Se(6) atoms. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ce(3), one Ce(4), and two equivalent Ce(2) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the second Se site, Se(2) is bonded to one Ce(3), one Ce(4), and two equivalent Ce(1) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the third Se site, Se(3) is bonded to one Ce(1), one Ce(2), and two equivalent Ce(4) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the fourth Se site, Se(4) is bonded to one Ce(1), one Ce(2), and two equivalent Ce(3) atoms to form a mixture of distorted edge and corner-sharing SeCe4 trigonal pyramids. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one Ce(1), one Ce(2), one Ce(3), one Ce(4), and two equivalent Se(5) atoms. In the sixth Se site, Se(6) is bonded in a 6-coordinate geometry to one Ce(1), one Ce(2), one Ce(3), one Ce(4), and two equivalent Se(6) atoms. is represented by the CIF file [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.884
_cell_length_b   5.641
_cell_length_c   16.472
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   639.626
_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  0.001  0.500  0.460  1.0
  Ce  Ce1  1  0.999  0.500  0.960  1.0
  Ce  Ce2  1  0.491  0.500  0.200  1.0
  Ce  Ce3  1  0.509  0.500  0.700  1.0
  Ce  Ce4  1  0.004  0.000  0.765  1.0
  Ce  Ce5  1  0.996  0.000  0.265  1.0
  Ce  Ce6  1  0.472  0.000  0.007  1.0
  Ce  Ce7  1  0.528  0.000  0.507  1.0
  Se  Se8  1  0.618  0.000  0.173  1.0
  Se  Se9  1  0.382  0.000  0.673  1.0
  Se  Se10  1  0.139  0.000  0.435  1.0
  Se  Se11  1  0.861  0.000  0.935  1.0
  Se  Se12  1  0.605  0.500  0.029  1.0
  Se  Se13  1  0.395  0.500  0.529  1.0
  Se  Se14  1  0.133  0.500  0.294  1.0
  Se  Se15  1  0.867  0.500  0.794  1.0
  Se  Se16  1  0.679  0.746  0.361  1.0
  Se  Se17  1  0.679  0.254  0.361  1.0
  Se  Se18  1  0.321  0.254  0.861  1.0
  Se  Se19  1  0.321  0.746  0.861  1.0
  Se  Se20  1  0.156  0.753  0.106  1.0
  Se  Se21  1  0.156  0.247  0.106  1.0
  Se  Se22  1  0.844  0.247  0.606  1.0
  Se  Se23  1  0.844  0.753  0.606  1.0
[/CIF]
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