The structure described by Ce4N2Se3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 2-coordinate geometry to two equivalent N(1), one Se(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. N(1) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form NCe4 tetrahedra that share corners with two equivalent Se(1)Ce6 octahedra, corners with six equivalent Se(2)Ce6 octahedra, corners with two equivalent N(1)Ce4 tetrahedra, edges with two equivalent Se(1)Ce6 octahedra, edges with three equivalent Se(2)Ce6 octahedra, and  an edgeedge with one N(1)Ce4 tetrahedra. The corner-sharing octahedral tilt angles range from 23-82°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ce(1) and four equivalent Ce(2) atoms to form SeCe6 octahedra that share corners with ten equivalent Se(2)Ce6 octahedra, corners with four equivalent N(1)Ce4 tetrahedra, edges with two equivalent Se(1)Ce6 octahedra, edges with four equivalent N(1)Ce4 tetrahedra, and faces with two equivalent Se(2)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 28-63°. In the second Se site, Se(2) is bonded to two equivalent Ce(2) and four equivalent Ce(1) atoms to form distorted SeCe6 octahedra that share corners with two equivalent Se(2)Ce6 octahedra, corners with five equivalent Se(1)Ce6 octahedra, corners with six equivalent N(1)Ce4 tetrahedra, edges with six equivalent Se(2)Ce6 octahedra, edges with three equivalent N(1)Ce4 tetrahedra, and  a faceface with one Se(1)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 18-63°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce4Se3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.336
_cell_length_b   8.336
_cell_length_c   6.504
_cell_angle_alpha   90.178
_cell_angle_beta   90.178
_cell_angle_gamma   75.509
_symmetry_Int_Tables_number   1
_cell_volume   437.559
_cell_formula_units_Z   2
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  0.807  0.444  0.029  1.0
  Ce  Ce1  1  0.556  0.193  0.471  1.0
  Ce  Ce2  1  0.193  0.556  0.971  1.0
  Ce  Ce3  1  0.444  0.807  0.529  1.0
  Ce  Ce4  1  0.241  0.089  0.075  1.0
  Ce  Ce5  1  0.911  0.759  0.425  1.0
  Ce  Ce6  1  0.759  0.911  0.925  1.0
  Ce  Ce7  1  0.089  0.241  0.575  1.0
  Se  Se8  1  0.902  0.098  0.250  1.0
  Se  Se9  1  0.098  0.902  0.750  1.0
  Se  Se10  1  0.486  0.748  0.038  1.0
  Se  Se11  1  0.252  0.514  0.462  1.0
  Se  Se12  1  0.514  0.252  0.962  1.0
  Se  Se13  1  0.748  0.486  0.538  1.0
  N  N14  1  0.919  0.669  0.083  1.0
  N  N15  1  0.331  0.081  0.417  1.0
  N  N16  1  0.081  0.331  0.917  1.0
  N  N17  1  0.669  0.919  0.583  1.0
[/CIF]
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The structure described by Ce4N2Se3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 2-coordinate geometry to two equivalent N(1), one Se(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. N(1) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form NCe4 tetrahedra that share corners with two equivalent Se(1)Ce6 octahedra, corners with six equivalent Se(2)Ce6 octahedra, corners with two equivalent N(1)Ce4 tetrahedra, edges with two equivalent Se(1)Ce6 octahedra, edges with three equivalent Se(2)Ce6 octahedra, and  an edgeedge with one N(1)Ce4 tetrahedra. The corner-sharing octahedral tilt angles range from 23-82°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ce(1) and four equivalent Ce(2) atoms to form SeCe6 octahedra that share corners with ten equivalent Se(2)Ce6 octahedra, corners with four equivalent N(1)Ce4 tetrahedra, edges with two equivalent Se(1)Ce6 octahedra, edges with four equivalent N(1)Ce4 tetrahedra, and faces with two equivalent Se(2)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 28-63°. In the second Se site, Se(2) is bonded to two equivalent Ce(2) and four equivalent Ce(1) atoms to form distorted SeCe6 octahedra that share corners with two equivalent Se(2)Ce6 octahedra, corners with five equivalent Se(1)Ce6 octahedra, corners with six equivalent N(1)Ce4 tetrahedra, edges with six equivalent Se(2)Ce6 octahedra, edges with three equivalent N(1)Ce4 tetrahedra, and  a faceface with one Se(1)Ce6 octahedra. The corner-sharing octahedral tilt angles range from 18-63°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce4Se3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.336
_cell_length_b   8.336
_cell_length_c   6.504
_cell_angle_alpha   90.178
_cell_angle_beta   90.178
_cell_angle_gamma   75.509
_symmetry_Int_Tables_number   1
_cell_volume   437.559
_cell_formula_units_Z   2
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  0.807  0.444  0.029  1.0
  Ce  Ce1  1  0.556  0.193  0.471  1.0
  Ce  Ce2  1  0.193  0.556  0.971  1.0
  Ce  Ce3  1  0.444  0.807  0.529  1.0
  Ce  Ce4  1  0.241  0.089  0.075  1.0
  Ce  Ce5  1  0.911  0.759  0.425  1.0
  Ce  Ce6  1  0.759  0.911  0.925  1.0
  Ce  Ce7  1  0.089  0.241  0.575  1.0
  Se  Se8  1  0.902  0.098  0.250  1.0
  Se  Se9  1  0.098  0.902  0.750  1.0
  Se  Se10  1  0.486  0.748  0.038  1.0
  Se  Se11  1  0.252  0.514  0.462  1.0
  Se  Se12  1  0.514  0.252  0.962  1.0
  Se  Se13  1  0.748  0.486  0.538  1.0
  N  N14  1  0.919  0.669  0.083  1.0
  N  N15  1  0.331  0.081  0.417  1.0
  N  N16  1  0.081  0.331  0.917  1.0
  N  N17  1  0.669  0.919  0.583  1.0
[/CIF]
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