The material described by CeSe2 is Low Tridymite-like structured and crystallizes in the tetragonal I-42m space group. Ce(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form corner-sharing CeSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. In the second Se site, Se(2) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the third Se site, Se(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Ce(1) atoms. is represented by the CIF card [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.964
_cell_length_b   12.964
_cell_length_c   12.964
_cell_angle_alpha   106.792
_cell_angle_beta   106.792
_cell_angle_gamma   114.973
_symmetry_Int_Tables_number   1
_cell_volume   1665.401
_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  0.886  0.120  0.642  1.0
  Ce  Ce1  1  0.478  0.245  0.358  1.0
  Ce  Ce2  1  0.114  0.755  0.233  1.0
  Ce  Ce3  1  0.522  0.880  0.767  1.0
  Ce  Ce4  1  0.755  0.114  0.233  1.0
  Ce  Ce5  1  0.880  0.522  0.767  1.0
  Ce  Ce6  1  0.245  0.478  0.358  1.0
  Ce  Ce7  1  0.120  0.886  0.642  1.0
  Se  Se8  1  0.372  0.372  0.291  1.0
  Se  Se9  1  0.081  0.081  0.709  1.0
  Se  Se10  1  0.628  0.919  0.000  1.0
  Se  Se11  1  0.919  0.628  0.000  1.0
  Se  Se12  1  0.716  0.000  0.716  1.0
  Se  Se13  1  0.284  0.000  0.284  1.0
  Se  Se14  1  0.000  0.284  0.284  1.0
  Se  Se15  1  0.000  0.716  0.716  1.0
  Se  Se16  1  0.983  0.377  0.746  1.0
  Se  Se17  1  0.631  0.237  0.254  1.0
  Se  Se18  1  0.017  0.763  0.394  1.0
  Se  Se19  1  0.369  0.623  0.606  1.0
  Se  Se20  1  0.763  0.017  0.394  1.0
  Se  Se21  1  0.623  0.369  0.606  1.0
  Se  Se22  1  0.237  0.631  0.254  1.0
  Se  Se23  1  0.377  0.983  0.746  1.0
[/CIF]
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The material described by CeSe2 is Low Tridymite-like structured and crystallizes in the tetragonal I-42m space group. Ce(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form corner-sharing CeSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a bent 150 degrees geometry to two equivalent Ce(1) atoms. In the second Se site, Se(2) is bonded in a linear geometry to two equivalent Ce(1) atoms. In the third Se site, Se(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Ce(1) atoms. is represented by the CIF card [CIF]
data_CeSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.964
_cell_length_b   12.964
_cell_length_c   12.964
_cell_angle_alpha   106.792
_cell_angle_beta   106.792
_cell_angle_gamma   114.973
_symmetry_Int_Tables_number   1
_cell_volume   1665.401
_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  0.886  0.120  0.642  1.0
  Ce  Ce1  1  0.478  0.245  0.358  1.0
  Ce  Ce2  1  0.114  0.755  0.233  1.0
  Ce  Ce3  1  0.522  0.880  0.767  1.0
  Ce  Ce4  1  0.755  0.114  0.233  1.0
  Ce  Ce5  1  0.880  0.522  0.767  1.0
  Ce  Ce6  1  0.245  0.478  0.358  1.0
  Ce  Ce7  1  0.120  0.886  0.642  1.0
  Se  Se8  1  0.372  0.372  0.291  1.0
  Se  Se9  1  0.081  0.081  0.709  1.0
  Se  Se10  1  0.628  0.919  0.000  1.0
  Se  Se11  1  0.919  0.628  0.000  1.0
  Se  Se12  1  0.716  0.000  0.716  1.0
  Se  Se13  1  0.284  0.000  0.284  1.0
  Se  Se14  1  0.000  0.284  0.284  1.0
  Se  Se15  1  0.000  0.716  0.716  1.0
  Se  Se16  1  0.983  0.377  0.746  1.0
  Se  Se17  1  0.631  0.237  0.254  1.0
  Se  Se18  1  0.017  0.763  0.394  1.0
  Se  Se19  1  0.369  0.623  0.606  1.0
  Se  Se20  1  0.763  0.017  0.394  1.0
  Se  Se21  1  0.623  0.369  0.606  1.0
  Se  Se22  1  0.237  0.631  0.254  1.0
  Se  Se23  1  0.377  0.983  0.746  1.0
[/CIF]
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