The structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the monoclinic C2/m space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(1), one Se(2), one Se(4), and one Se(7) atom to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(1), one Se(3), one Se(6), and one Se(9) atom to form corner-sharing CeSe4 tetrahedra. In the third Ce site, Ce(3) is bonded to one Se(10), one Se(5), one Se(6), and one Se(8) atom to form corner-sharing CeSe4 tetrahedra. In the fourth Ce site, Ce(4) is bonded to one Se(2), one Se(3), one Se(5), and one Se(8) atom to form corner-sharing CeSe4 tetrahedra. There are ten inequivalent Se sites. In the first Se site, Se(1) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the second Se site, Se(2) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(4) atom. In the third Se site, Se(3) is bonded in a bent 150 degrees geometry to one Ce(2) and one Ce(4) atom. In the fourth Se site, Se(4) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the fifth Se site, Se(5) is bonded in a bent 150 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(2) and one Ce(3) atom. In the seventh Se site, Se(7) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. In the eighth Se site, Se(8) is bonded in a bent 150 degrees geometry to one Ce(3) and one Ce(4) atom. In the ninth Se site, Se(9) is bonded in a bent 150 degrees geometry to two equivalent Ce(2) atoms. In the tenth Se site, Se(10) is bonded in a bent 150 degrees geometry to two equivalent Ce(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.007
_cell_length_b   19.600
_cell_length_c   19.600
_cell_angle_alpha   71.457
_cell_angle_beta   80.426
_cell_angle_gamma   80.426
_symmetry_Int_Tables_number   1
_cell_volume   4636.601
_cell_formula_units_Z   16
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  0.301  0.601  0.374  1.0
  Ce  Ce1  1  0.301  0.374  0.601  1.0
  Ce  Ce2  1  0.699  0.399  0.626  1.0
  Ce  Ce3  1  0.699  0.626  0.399  1.0
  Ce  Ce4  1  0.099  0.762  0.533  1.0
  Ce  Ce5  1  0.099  0.533  0.762  1.0
  Ce  Ce6  1  0.901  0.238  0.467  1.0
  Ce  Ce7  1  0.901  0.467  0.238  1.0
  Ce  Ce8  1  0.622  0.364  0.138  1.0
  Ce  Ce9  1  0.622  0.138  0.364  1.0
  Ce  Ce10  1  0.378  0.636  0.862  1.0
  Ce  Ce11  1  0.378  0.862  0.636  1.0
  Ce  Ce12  1  0.272  0.542  0.135  1.0
  Ce  Ce13  1  0.272  0.135  0.542  1.0
  Ce  Ce14  1  0.728  0.458  0.865  1.0
  Ce  Ce15  1  0.728  0.865  0.458  1.0
  Se  Se16  1  0.171  0.706  0.421  1.0
  Se  Se17  1  0.171  0.421  0.706  1.0
  Se  Se18  1  0.829  0.294  0.579  1.0
  Se  Se19  1  0.829  0.579  0.294  1.0
  Se  Se20  1  0.265  0.610  0.238  1.0
  Se  Se21  1  0.265  0.238  0.610  1.0
  Se  Se22  1  0.735  0.390  0.762  1.0
  Se  Se23  1  0.735  0.762  0.390  1.0
  Se  Se24  1  0.921  0.855  0.498  1.0
  Se  Se25  1  0.921  0.498  0.855  1.0
  Se  Se26  1  0.079  0.145  0.502  1.0
  Se  Se27  1  0.079  0.502  0.145  1.0
  Se  Se28  1  0.500  0.626  0.374  1.0
  Se  Se29  1  0.500  0.374  0.626  1.0
  Se  Se30  1  0.418  0.424  0.157  1.0
  Se  Se31  1  0.418  0.157  0.424  1.0
  Se  Se32  1  0.582  0.576  0.843  1.0
  Se  Se33  1  0.582  0.843  0.576  1.0
  Se  Se34  1  0.249  0.831  0.557  1.0
  Se  Se35  1  0.249  0.557  0.831  1.0
  Se  Se36  1  0.751  0.169  0.443  1.0
  Se  Se37  1  0.751  0.443  0.169  1.0
  Se  Se38  1  0.275  0.469  0.469  1.0
  Se  Se39  1  0.725  0.531  0.531  1.0
  Se  Se40  1  0.679  0.363  0.999  1.0
  Se  Se41  1  0.679  0.999  0.363  1.0
  Se  Se42  1  0.321  0.637  0.001  1.0
  Se  Se43  1  0.321  0.001  0.637  1.0
  Se  Se44  1  0.045  0.656  0.656  1.0
  Se  Se45  1  0.955  0.344  0.344  1.0
  Se  Se46  1  0.645  0.223  0.223  1.0
  Se  Se47  1  0.355  0.777  0.777  1.0
[/CIF]
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The structure described by CeSe2 is Low Tridymite-like structured and crystallizes in the monoclinic C2/m space group. There are four inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one Se(1), one Se(2), one Se(4), and one Se(7) atom to form corner-sharing CeSe4 tetrahedra. In the second Ce site, Ce(2) is bonded to one Se(1), one Se(3), one Se(6), and one Se(9) atom to form corner-sharing CeSe4 tetrahedra. In the third Ce site, Ce(3) is bonded to one Se(10), one Se(5), one Se(6), and one Se(8) atom to form corner-sharing CeSe4 tetrahedra. In the fourth Ce site, Ce(4) is bonded to one Se(2), one Se(3), one Se(5), and one Se(8) atom to form corner-sharing CeSe4 tetrahedra. There are ten inequivalent Se sites. In the first Se site, Se(1) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(2) atom. In the second Se site, Se(2) is bonded in a bent 150 degrees geometry to one Ce(1) and one Ce(4) atom. In the third Se site, Se(3) is bonded in a bent 150 degrees geometry to one Ce(2) and one Ce(4) atom. In the fourth Se site, Se(4) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the fifth Se site, Se(5) is bonded in a bent 150 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(2) and one Ce(3) atom. In the seventh Se site, Se(7) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. In the eighth Se site, Se(8) is bonded in a bent 150 degrees geometry to one Ce(3) and one Ce(4) atom. In the ninth Se site, Se(9) is bonded in a bent 150 degrees geometry to two equivalent Ce(2) atoms. In the tenth Se site, Se(10) is bonded in a bent 150 degrees geometry to two equivalent Ce(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.007
_cell_length_b   19.600
_cell_length_c   19.600
_cell_angle_alpha   71.457
_cell_angle_beta   80.426
_cell_angle_gamma   80.426
_symmetry_Int_Tables_number   1
_cell_volume   4636.601
_cell_formula_units_Z   16
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  0.301  0.601  0.374  1.0
  Ce  Ce1  1  0.301  0.374  0.601  1.0
  Ce  Ce2  1  0.699  0.399  0.626  1.0
  Ce  Ce3  1  0.699  0.626  0.399  1.0
  Ce  Ce4  1  0.099  0.762  0.533  1.0
  Ce  Ce5  1  0.099  0.533  0.762  1.0
  Ce  Ce6  1  0.901  0.238  0.467  1.0
  Ce  Ce7  1  0.901  0.467  0.238  1.0
  Ce  Ce8  1  0.622  0.364  0.138  1.0
  Ce  Ce9  1  0.622  0.138  0.364  1.0
  Ce  Ce10  1  0.378  0.636  0.862  1.0
  Ce  Ce11  1  0.378  0.862  0.636  1.0
  Ce  Ce12  1  0.272  0.542  0.135  1.0
  Ce  Ce13  1  0.272  0.135  0.542  1.0
  Ce  Ce14  1  0.728  0.458  0.865  1.0
  Ce  Ce15  1  0.728  0.865  0.458  1.0
  Se  Se16  1  0.171  0.706  0.421  1.0
  Se  Se17  1  0.171  0.421  0.706  1.0
  Se  Se18  1  0.829  0.294  0.579  1.0
  Se  Se19  1  0.829  0.579  0.294  1.0
  Se  Se20  1  0.265  0.610  0.238  1.0
  Se  Se21  1  0.265  0.238  0.610  1.0
  Se  Se22  1  0.735  0.390  0.762  1.0
  Se  Se23  1  0.735  0.762  0.390  1.0
  Se  Se24  1  0.921  0.855  0.498  1.0
  Se  Se25  1  0.921  0.498  0.855  1.0
  Se  Se26  1  0.079  0.145  0.502  1.0
  Se  Se27  1  0.079  0.502  0.145  1.0
  Se  Se28  1  0.500  0.626  0.374  1.0
  Se  Se29  1  0.500  0.374  0.626  1.0
  Se  Se30  1  0.418  0.424  0.157  1.0
  Se  Se31  1  0.418  0.157  0.424  1.0
  Se  Se32  1  0.582  0.576  0.843  1.0
  Se  Se33  1  0.582  0.843  0.576  1.0
  Se  Se34  1  0.249  0.831  0.557  1.0
  Se  Se35  1  0.249  0.557  0.831  1.0
  Se  Se36  1  0.751  0.169  0.443  1.0
  Se  Se37  1  0.751  0.443  0.169  1.0
  Se  Se38  1  0.275  0.469  0.469  1.0
  Se  Se39  1  0.725  0.531  0.531  1.0
  Se  Se40  1  0.679  0.363  0.999  1.0
  Se  Se41  1  0.679  0.999  0.363  1.0
  Se  Se42  1  0.321  0.637  0.001  1.0
  Se  Se43  1  0.321  0.001  0.637  1.0
  Se  Se44  1  0.045  0.656  0.656  1.0
  Se  Se45  1  0.955  0.344  0.344  1.0
  Se  Se46  1  0.645  0.223  0.223  1.0
  Se  Se47  1  0.355  0.777  0.777  1.0
[/CIF]
.