The crystal structure described by Ce5CuSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second Ce site, Ce(2) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Cu(1) is bonded in a square co-planar geometry to four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ce(2) and four equivalent Ce(1) atoms to form distorted SeCe5 square pyramids that share corners with eight equivalent Se(2)Ce5Cu octahedra, corners with five equivalent Se(1)Ce5 square pyramids, edges with three equivalent Se(2)Ce5Cu octahedra, edges with five equivalent Se(1)Ce5 square pyramids, and faces with two equivalent Se(2)Ce5Cu octahedra. The corner-sharing octahedral tilt angles range from 19-88°. In the second Se site, Se(2) is bonded to one Ce(2), four equivalent Ce(1), and one Cu(1) atom to form distorted SeCe5Cu octahedra that share corners with seven equivalent Se(2)Ce5Cu octahedra, corners with eight equivalent Se(1)Ce5 square pyramids, edges with four equivalent Se(2)Ce5Cu octahedra, edges with three equivalent Se(1)Ce5 square pyramids,  a faceface with one Se(2)Ce5Cu octahedra, and faces with two equivalent Se(1)Ce5 square pyramids. The corner-sharing octahedral tilt angles range from 16-48°. is represented by the CIF card [CIF]
data_Ce5CuSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.679
_cell_length_b   7.679
_cell_length_c   7.679
_cell_angle_alpha   110.446
_cell_angle_beta   110.446
_cell_angle_gamma   107.538
_symmetry_Int_Tables_number   1
_cell_volume   348.264
_cell_formula_units_Z   1
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  0.116  0.239  0.622  1.0
  Ce  Ce1  1  0.250  0.750  0.500  1.0
  Ce  Ce2  1  0.617  0.494  0.378  1.0
  Ce  Ce3  1  0.506  0.884  0.123  1.0
  Ce  Ce4  1  0.761  0.383  0.877  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.864  0.764  0.261  1.0
  Se  Se7  1  0.396  0.136  0.899  1.0
  Se  Se8  1  0.023  0.652  0.758  1.0
  Se  Se9  1  0.236  0.497  0.101  1.0
  Se  Se10  1  0.348  0.106  0.371  1.0
  Se  Se11  1  0.503  0.604  0.739  1.0
  Se  Se12  1  0.735  0.977  0.629  1.0
  Se  Se13  1  0.894  0.265  0.242  1.0
[/CIF]
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The crystal structure described by Ce5CuSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second Ce site, Ce(2) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Cu(1) is bonded in a square co-planar geometry to four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ce(2) and four equivalent Ce(1) atoms to form distorted SeCe5 square pyramids that share corners with eight equivalent Se(2)Ce5Cu octahedra, corners with five equivalent Se(1)Ce5 square pyramids, edges with three equivalent Se(2)Ce5Cu octahedra, edges with five equivalent Se(1)Ce5 square pyramids, and faces with two equivalent Se(2)Ce5Cu octahedra. The corner-sharing octahedral tilt angles range from 19-88°. In the second Se site, Se(2) is bonded to one Ce(2), four equivalent Ce(1), and one Cu(1) atom to form distorted SeCe5Cu octahedra that share corners with seven equivalent Se(2)Ce5Cu octahedra, corners with eight equivalent Se(1)Ce5 square pyramids, edges with four equivalent Se(2)Ce5Cu octahedra, edges with three equivalent Se(1)Ce5 square pyramids,  a faceface with one Se(2)Ce5Cu octahedra, and faces with two equivalent Se(1)Ce5 square pyramids. The corner-sharing octahedral tilt angles range from 16-48°. is represented by the CIF card [CIF]
data_Ce5CuSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.679
_cell_length_b   7.679
_cell_length_c   7.679
_cell_angle_alpha   110.446
_cell_angle_beta   110.446
_cell_angle_gamma   107.538
_symmetry_Int_Tables_number   1
_cell_volume   348.264
_cell_formula_units_Z   1
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  0.116  0.239  0.622  1.0
  Ce  Ce1  1  0.250  0.750  0.500  1.0
  Ce  Ce2  1  0.617  0.494  0.378  1.0
  Ce  Ce3  1  0.506  0.884  0.123  1.0
  Ce  Ce4  1  0.761  0.383  0.877  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.864  0.764  0.261  1.0
  Se  Se7  1  0.396  0.136  0.899  1.0
  Se  Se8  1  0.023  0.652  0.758  1.0
  Se  Se9  1  0.236  0.497  0.101  1.0
  Se  Se10  1  0.348  0.106  0.371  1.0
  Se  Se11  1  0.503  0.604  0.739  1.0
  Se  Se12  1  0.735  0.977  0.629  1.0
  Se  Se13  1  0.894  0.265  0.242  1.0
[/CIF]
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