The material described by Ce4N2Se3 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 6-coordinate geometry to two equivalent N(1) and four equivalent Se(2) atoms. In the second Ce site, Ce(2) is bonded in a 6-coordinate geometry to two equivalent N(1), two equivalent Se(1), and two equivalent Se(2) atoms. In the third Ce site, Ce(3) is bonded in a 2-coordinate geometry to two equivalent N(1), two equivalent Se(1), and three equivalent Se(2) atoms. N(1) is bonded to one Ce(1), one Ce(2), and two equivalent Ce(3) atoms to form NCe4 tetrahedra that share corners with four equivalent Se(1)Ce6 octahedra, corners with six equivalent Se(2)Ce6 octahedra,  an edgeedge with one Se(1)Ce6 octahedra, edges with three equivalent Se(2)Ce6 octahedra, and edges with two equivalent N(1)Ce4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-92°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ce(2) and four equivalent Ce(3) atoms to form SeCe6 octahedra that share corners with eight equivalent Se(2)Ce6 octahedra, corners with eight equivalent N(1)Ce4 tetrahedra, edges with four equivalent Se(2)Ce6 octahedra, edges with two equivalent N(1)Ce4 tetrahedra, and faces with two equivalent Se(1)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 39-84°. In the second Se site, Se(2) is bonded to one Ce(2), two equivalent Ce(1), and three equivalent Ce(3) atoms to form distorted SeCe6 octahedra that share corners with four equivalent Se(1)Ce6 octahedra, corners with four equivalent Se(2)Ce6 octahedra, corners with six equivalent N(1)Ce4 tetrahedra, edges with two equivalent Se(1)Ce6 octahedra, edges with three equivalent Se(2)Ce6 octahedra, edges with three equivalent N(1)Ce4 tetrahedra, and  a faceface with one Se(2)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 30-84°. is represented by the CIF file [CIF]
data_Ce4Se3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.022
_cell_length_b   10.927
_cell_length_c   11.385
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   873.505
_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  0.598  0.835  0.750  1.0
  Ce  Ce1  1  0.098  0.665  0.750  1.0
  Ce  Ce2  1  0.402  0.165  0.250  1.0
  Ce  Ce3  1  0.902  0.335  0.250  1.0
  Ce  Ce4  1  0.711  0.468  0.750  1.0
  Ce  Ce5  1  0.211  0.032  0.750  1.0
  Ce  Ce6  1  0.289  0.532  0.250  1.0
  Ce  Ce7  1  0.789  0.968  0.250  1.0
  Ce  Ce8  1  0.661  0.114  0.948  1.0
  Ce  Ce9  1  0.161  0.386  0.552  1.0
  Ce  Ce10  1  0.339  0.886  0.448  1.0
  Ce  Ce11  1  0.839  0.614  0.052  1.0
  Ce  Ce12  1  0.339  0.886  0.052  1.0
  Ce  Ce13  1  0.839  0.614  0.448  1.0
  Ce  Ce14  1  0.661  0.114  0.552  1.0
  Ce  Ce15  1  0.161  0.386  0.948  1.0
  Se  Se16  1  0.923  0.235  0.750  1.0
  Se  Se17  1  0.423  0.265  0.750  1.0
  Se  Se18  1  0.077  0.765  0.250  1.0
  Se  Se19  1  0.577  0.735  0.250  1.0
  Se  Se20  1  0.564  0.363  0.081  1.0
  Se  Se21  1  0.064  0.137  0.419  1.0
  Se  Se22  1  0.436  0.637  0.581  1.0
  Se  Se23  1  0.936  0.863  0.919  1.0
  Se  Se24  1  0.436  0.637  0.919  1.0
  Se  Se25  1  0.936  0.863  0.581  1.0
  Se  Se26  1  0.564  0.363  0.419  1.0
  Se  Se27  1  0.064  0.137  0.081  1.0
  N  N28  1  0.557  0.035  0.121  1.0
  N  N29  1  0.057  0.465  0.378  1.0
  N  N30  1  0.443  0.965  0.622  1.0
  N  N31  1  0.943  0.535  0.879  1.0
  N  N32  1  0.443  0.965  0.878  1.0
  N  N33  1  0.943  0.535  0.622  1.0
  N  N34  1  0.557  0.035  0.378  1.0
  N  N35  1  0.057  0.465  0.121  1.0
[/CIF]
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The material described by Ce4N2Se3 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 6-coordinate geometry to two equivalent N(1) and four equivalent Se(2) atoms. In the second Ce site, Ce(2) is bonded in a 6-coordinate geometry to two equivalent N(1), two equivalent Se(1), and two equivalent Se(2) atoms. In the third Ce site, Ce(3) is bonded in a 2-coordinate geometry to two equivalent N(1), two equivalent Se(1), and three equivalent Se(2) atoms. N(1) is bonded to one Ce(1), one Ce(2), and two equivalent Ce(3) atoms to form NCe4 tetrahedra that share corners with four equivalent Se(1)Ce6 octahedra, corners with six equivalent Se(2)Ce6 octahedra,  an edgeedge with one Se(1)Ce6 octahedra, edges with three equivalent Se(2)Ce6 octahedra, and edges with two equivalent N(1)Ce4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-92°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ce(2) and four equivalent Ce(3) atoms to form SeCe6 octahedra that share corners with eight equivalent Se(2)Ce6 octahedra, corners with eight equivalent N(1)Ce4 tetrahedra, edges with four equivalent Se(2)Ce6 octahedra, edges with two equivalent N(1)Ce4 tetrahedra, and faces with two equivalent Se(1)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 39-84°. In the second Se site, Se(2) is bonded to one Ce(2), two equivalent Ce(1), and three equivalent Ce(3) atoms to form distorted SeCe6 octahedra that share corners with four equivalent Se(1)Ce6 octahedra, corners with four equivalent Se(2)Ce6 octahedra, corners with six equivalent N(1)Ce4 tetrahedra, edges with two equivalent Se(1)Ce6 octahedra, edges with three equivalent Se(2)Ce6 octahedra, edges with three equivalent N(1)Ce4 tetrahedra, and  a faceface with one Se(2)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 30-84°. is represented by the CIF file [CIF]
data_Ce4Se3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.022
_cell_length_b   10.927
_cell_length_c   11.385
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   873.505
_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  0.598  0.835  0.750  1.0
  Ce  Ce1  1  0.098  0.665  0.750  1.0
  Ce  Ce2  1  0.402  0.165  0.250  1.0
  Ce  Ce3  1  0.902  0.335  0.250  1.0
  Ce  Ce4  1  0.711  0.468  0.750  1.0
  Ce  Ce5  1  0.211  0.032  0.750  1.0
  Ce  Ce6  1  0.289  0.532  0.250  1.0
  Ce  Ce7  1  0.789  0.968  0.250  1.0
  Ce  Ce8  1  0.661  0.114  0.948  1.0
  Ce  Ce9  1  0.161  0.386  0.552  1.0
  Ce  Ce10  1  0.339  0.886  0.448  1.0
  Ce  Ce11  1  0.839  0.614  0.052  1.0
  Ce  Ce12  1  0.339  0.886  0.052  1.0
  Ce  Ce13  1  0.839  0.614  0.448  1.0
  Ce  Ce14  1  0.661  0.114  0.552  1.0
  Ce  Ce15  1  0.161  0.386  0.948  1.0
  Se  Se16  1  0.923  0.235  0.750  1.0
  Se  Se17  1  0.423  0.265  0.750  1.0
  Se  Se18  1  0.077  0.765  0.250  1.0
  Se  Se19  1  0.577  0.735  0.250  1.0
  Se  Se20  1  0.564  0.363  0.081  1.0
  Se  Se21  1  0.064  0.137  0.419  1.0
  Se  Se22  1  0.436  0.637  0.581  1.0
  Se  Se23  1  0.936  0.863  0.919  1.0
  Se  Se24  1  0.436  0.637  0.919  1.0
  Se  Se25  1  0.936  0.863  0.581  1.0
  Se  Se26  1  0.564  0.363  0.419  1.0
  Se  Se27  1  0.064  0.137  0.081  1.0
  N  N28  1  0.557  0.035  0.121  1.0
  N  N29  1  0.057  0.465  0.378  1.0
  N  N30  1  0.443  0.965  0.622  1.0
  N  N31  1  0.943  0.535  0.879  1.0
  N  N32  1  0.443  0.965  0.878  1.0
  N  N33  1  0.943  0.535  0.622  1.0
  N  N34  1  0.557  0.035  0.378  1.0
  N  N35  1  0.057  0.465  0.121  1.0
[/CIF]
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