The crystal structure described by Cr8CoCu3Se16 is Spinel-derived structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(4) atoms to form CrSe6 octahedra that share  a cornercorner with one Co(1)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, edges with two equivalent Cr(2)Se6 octahedra, and edges with four equivalent Cr(1)Se6 octahedra. In the second Cr site, Cr(2) is bonded to one Se(2), two equivalent Se(1), and three equivalent Se(3) atoms to form CrSe6 octahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra, corners with two equivalent Co(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, edges with two equivalent Cr(1)Se6 octahedra, and edges with four equivalent Cr(2)Se6 octahedra. Co(1) is bonded to four equivalent Se(1) atoms to form CoSe4 tetrahedra that share corners with four equivalent Cr(1)Se6 octahedra and corners with eight equivalent Cr(2)Se6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Se(2) atoms to form CuSe4 tetrahedra that share corners with four equivalent Cr(2)Se6 octahedra and corners with eight equivalent Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Cu site, Cu(2) is bonded to two equivalent Se(3) and two equivalent Se(4) atoms to form CuSe4 tetrahedra that share corners with six equivalent Cr(1)Se6 octahedra and corners with six equivalent Cr(2)Se6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted rectangular see-saw-like geometry to one Cr(1), two equivalent Cr(2), and one Co(1) atom. In the second Se site, Se(2) is bonded to one Cr(2), two equivalent Cr(1), and one Cu(1) atom to form a mixture of distorted edge and corner-sharing SeCr3Cu trigonal pyramids. In the third Se site, Se(3) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr(2) and one Cu(2) atom. In the fourth Se site, Se(4) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr(1) and one Cu(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr8CoCu3Se16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.373
_cell_length_b   7.373
_cell_length_c   10.422
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   566.527
_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
  Cr  Cr0  1  0.250  0.500  0.124  1.0
  Cr  Cr1  1  0.753  0.000  0.625  1.0
  Cr  Cr2  1  0.750  0.500  0.124  1.0
  Cr  Cr3  1  0.247  0.000  0.625  1.0
  Cr  Cr4  1  0.000  0.247  0.375  1.0
  Cr  Cr5  1  0.500  0.750  0.876  1.0
  Cr  Cr6  1  0.500  0.250  0.876  1.0
  Cr  Cr7  1  0.000  0.753  0.375  1.0
  Co  Co8  1  0.500  0.500  0.500  1.0
  Cu  Cu9  1  0.000  0.000  0.000  1.0
  Cu  Cu10  1  0.500  0.000  0.250  1.0
  Cu  Cu11  1  0.000  0.500  0.750  1.0
  Se  Se12  1  0.762  0.500  0.369  1.0
  Se  Se13  1  0.266  0.000  0.867  1.0
  Se  Se14  1  0.238  0.500  0.369  1.0
  Se  Se15  1  0.734  0.000  0.867  1.0
  Se  Se16  1  0.500  0.238  0.631  1.0
  Se  Se17  1  0.000  0.734  0.133  1.0
  Se  Se18  1  0.500  0.762  0.631  1.0
  Se  Se19  1  0.000  0.266  0.133  1.0
  Se  Se20  1  0.235  0.000  0.383  1.0
  Se  Se21  1  0.735  0.500  0.883  1.0
  Se  Se22  1  0.765  0.000  0.383  1.0
  Se  Se23  1  0.265  0.500  0.883  1.0
  Se  Se24  1  0.500  0.265  0.117  1.0
  Se  Se25  1  0.000  0.765  0.617  1.0
  Se  Se26  1  0.500  0.735  0.117  1.0
  Se  Se27  1  0.000  0.235  0.617  1.0
[/CIF]
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The crystal structure described by Cr8CoCu3Se16 is Spinel-derived structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(4) atoms to form CrSe6 octahedra that share  a cornercorner with one Co(1)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, edges with two equivalent Cr(2)Se6 octahedra, and edges with four equivalent Cr(1)Se6 octahedra. In the second Cr site, Cr(2) is bonded to one Se(2), two equivalent Se(1), and three equivalent Se(3) atoms to form CrSe6 octahedra that share  a cornercorner with one Cu(1)Se4 tetrahedra, corners with two equivalent Co(1)Se4 tetrahedra, corners with three equivalent Cu(2)Se4 tetrahedra, edges with two equivalent Cr(1)Se6 octahedra, and edges with four equivalent Cr(2)Se6 octahedra. Co(1) is bonded to four equivalent Se(1) atoms to form CoSe4 tetrahedra that share corners with four equivalent Cr(1)Se6 octahedra and corners with eight equivalent Cr(2)Se6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Se(2) atoms to form CuSe4 tetrahedra that share corners with four equivalent Cr(2)Se6 octahedra and corners with eight equivalent Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Cu site, Cu(2) is bonded to two equivalent Se(3) and two equivalent Se(4) atoms to form CuSe4 tetrahedra that share corners with six equivalent Cr(1)Se6 octahedra and corners with six equivalent Cr(2)Se6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted rectangular see-saw-like geometry to one Cr(1), two equivalent Cr(2), and one Co(1) atom. In the second Se site, Se(2) is bonded to one Cr(2), two equivalent Cr(1), and one Cu(1) atom to form a mixture of distorted edge and corner-sharing SeCr3Cu trigonal pyramids. In the third Se site, Se(3) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr(2) and one Cu(2) atom. In the fourth Se site, Se(4) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr(1) and one Cu(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr8CoCu3Se16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.373
_cell_length_b   7.373
_cell_length_c   10.422
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   566.527
_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
  Cr  Cr0  1  0.250  0.500  0.124  1.0
  Cr  Cr1  1  0.753  0.000  0.625  1.0
  Cr  Cr2  1  0.750  0.500  0.124  1.0
  Cr  Cr3  1  0.247  0.000  0.625  1.0
  Cr  Cr4  1  0.000  0.247  0.375  1.0
  Cr  Cr5  1  0.500  0.750  0.876  1.0
  Cr  Cr6  1  0.500  0.250  0.876  1.0
  Cr  Cr7  1  0.000  0.753  0.375  1.0
  Co  Co8  1  0.500  0.500  0.500  1.0
  Cu  Cu9  1  0.000  0.000  0.000  1.0
  Cu  Cu10  1  0.500  0.000  0.250  1.0
  Cu  Cu11  1  0.000  0.500  0.750  1.0
  Se  Se12  1  0.762  0.500  0.369  1.0
  Se  Se13  1  0.266  0.000  0.867  1.0
  Se  Se14  1  0.238  0.500  0.369  1.0
  Se  Se15  1  0.734  0.000  0.867  1.0
  Se  Se16  1  0.500  0.238  0.631  1.0
  Se  Se17  1  0.000  0.734  0.133  1.0
  Se  Se18  1  0.500  0.762  0.631  1.0
  Se  Se19  1  0.000  0.266  0.133  1.0
  Se  Se20  1  0.235  0.000  0.383  1.0
  Se  Se21  1  0.735  0.500  0.883  1.0
  Se  Se22  1  0.765  0.000  0.383  1.0
  Se  Se23  1  0.265  0.500  0.883  1.0
  Se  Se24  1  0.500  0.265  0.117  1.0
  Se  Se25  1  0.000  0.765  0.617  1.0
  Se  Se26  1  0.500  0.735  0.117  1.0
  Se  Se27  1  0.000  0.235  0.617  1.0
[/CIF]
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