The compound described by Cr8FeZn3Se16 is Spinel-derived structured and crystallizes in the trigonal R3m space group. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three equivalent Se(3) and three equivalent Se(8) atoms to form CrSe6 octahedra that share corners with three equivalent Fe(1)Se4 tetrahedra, corners with three equivalent Zn(3)Se4 tetrahedra, edges with three equivalent Cr(3)Se6 octahedra, and edges with three equivalent Cr(4)Se6 octahedra. In the second Cr site, Cr(2) is bonded to three equivalent Se(4) and three equivalent Se(7) atoms to form CrSe6 octahedra that share corners with three equivalent Zn(1)Se4 tetrahedra, corners with three equivalent Zn(2)Se4 tetrahedra, edges with three equivalent Cr(3)Se6 octahedra, and edges with three equivalent Cr(4)Se6 octahedra. In the third Cr site, Cr(3) is bonded to one Se(1), one Se(5), two equivalent Se(3), and two equivalent Se(7) atoms to form CrSe6 octahedra that share  a cornercorner with one Zn(1)Se4 tetrahedra,  a cornercorner with one Zn(3)Se4 tetrahedra, corners with two equivalent Fe(1)Se4 tetrahedra, corners with two equivalent Zn(2)Se4 tetrahedra,  an edgeedge with one Cr(1)Se6 octahedra,  an edgeedge with one Cr(2)Se6 octahedra, and edges with four equivalent Cr(3)Se6 octahedra. In the fourth Cr site, Cr(4) is bonded to one Se(2), one Se(6), two equivalent Se(4), and two equivalent Se(8) atoms to form CrSe6 octahedra that share  a cornercorner with one Fe(1)Se4 tetrahedra,  a cornercorner with one Zn(2)Se4 tetrahedra, corners with two equivalent Zn(1)Se4 tetrahedra, corners with two equivalent Zn(3)Se4 tetrahedra,  an edgeedge with one Cr(1)Se6 octahedra,  an edgeedge with one Cr(2)Se6 octahedra, and edges with four equivalent Cr(4)Se6 octahedra. Fe(1) is bonded to one Se(2) and three equivalent Se(3) atoms to form FeSe4 tetrahedra that share corners with three equivalent Cr(1)Se6 octahedra, corners with three equivalent Cr(4)Se6 octahedra, and corners with six equivalent Cr(3)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one Se(1) and three equivalent Se(4) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Cr(2)Se6 octahedra, corners with three equivalent Cr(3)Se6 octahedra, and corners with six equivalent Cr(4)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Zn site, Zn(2) is bonded to one Se(6) and three equivalent Se(7) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Cr(2)Se6 octahedra, corners with three equivalent Cr(4)Se6 octahedra, and corners with six equivalent Cr(3)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the third Zn site, Zn(3) is bonded to one Se(5) and three equivalent Se(8) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Cr(1)Se6 octahedra, corners with three equivalent Cr(3)Se6 octahedra, and corners with six equivalent Cr(4)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Cr(3) and one Zn(1) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(4)ZnCr3 trigonal pyramids, corners with three equivalent Se(5)ZnCr3 trigonal pyramids, corners with six equivalent Se(7)ZnCr3 trigonal pyramids, and edges with three equivalent Se(3)Cr3Fe trigonal pyramids. In the second Se site, Se(2) is bonded to three equivalent Cr(4) and one Fe(1) atom to form distorted SeCr3Fe trigonal pyramids that share corners with three equivalent Se(3)Cr3Fe trigonal pyramids, corners with three equivalent Se(6)ZnCr3 trigonal pyramids, corners with six equivalent Se(8)ZnCr3 trigonal pyramids, and edges with three equivalent Se(4)ZnCr3 trigonal pyramids. In the third Se site, Se(3) is bonded to one Cr(1), two equivalent Cr(3), and one Fe(1) atom to form distorted SeCr3Fe trigonal pyramids that share  a cornercorner with one Se(2)Cr3Fe trigonal pyramid, corners with two equivalent Se(3)Cr3Fe trigonal pyramids, corners with two equivalent Se(5)ZnCr3 trigonal pyramids, corners with three equivalent Se(8)ZnCr3 trigonal pyramids, corners with four equivalent Se(7)ZnCr3 trigonal pyramids,  an edgeedge with one Se(1)ZnCr3 trigonal pyramid, and edges with two equivalent Se(3)Cr3Fe trigonal pyramids. In the fourth Se site, Se(4) is bonded to one Cr(2), two equivalent Cr(4), and one Zn(1) atom to form distorted SeZnCr3 trigonal pyramids that share  a cornercorner with one Se(1)ZnCr3 trigonal pyramid, corners with two equivalent Se(4)ZnCr3 trigonal pyramids, corners with two equivalent Se(6)ZnCr3 trigonal pyramids, corners with three equivalent Se(7)ZnCr3 trigonal pyramids, corners with four equivalent Se(8)ZnCr3 trigonal pyramids,  an edgeedge with one Se(2)Cr3Fe trigonal pyramid, and edges with two equivalent Se(4)ZnCr3 trigonal pyramids. In the fifth Se site, Se(5) is bonded to three equivalent Cr(3) and one Zn(3) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(1)ZnCr3 trigonal pyramids, corners with three equivalent Se(8)ZnCr3 trigonal pyramids, corners with six equivalent Se(3)Cr3Fe trigonal pyramids, and edges with three equivalent Se(7)ZnCr3 trigonal pyramids. In the sixth Se site, Se(6) is bonded to three equivalent Cr(4) and one Zn(2) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(2)Cr3Fe trigonal pyramids, corners with three equivalent Se(7)ZnCr3 trigonal pyramids, corners with six equivalent Se(4)ZnCr3 trigonal pyramids, and edges with three equivalent Se(8)ZnCr3 trigonal pyramids. In the seventh Se site, Se(7) is bonded to one Cr(2), two equivalent Cr(3), and one Zn(2) atom to form distorted SeZnCr3 trigonal pyramids that share  a cornercorner with one Se(6)ZnCr3 trigonal pyramid, corners with two equivalent Se(1)ZnCr3 trigonal pyramids, corners with two equivalent Se(7)ZnCr3 trigonal pyramids, corners with three equivalent Se(4)ZnCr3 trigonal pyramids, corners with four equivalent Se(3)Cr3Fe trigonal pyramids,  an edgeedge with one Se(5)ZnCr3 trigonal pyramid, and edges with two equivalent Se(7)ZnCr3 trigonal pyramids. In the eighth Se site, Se(8) is bonded to one Cr(1), two equivalent Cr(4), and one Zn(3) atom to form distorted SeZnCr3 trigonal pyramids that share  a cornercorner with one Se(5)ZnCr3 trigonal pyramid, corners with two equivalent Se(2)Cr3Fe trigonal pyramids, corners with two equivalent Se(8)ZnCr3 trigonal pyramids, corners with three equivalent Se(3)Cr3Fe trigonal pyramids, corners with four equivalent Se(4)ZnCr3 trigonal pyramids,  an edgeedge with one Se(6)ZnCr3 trigonal pyramid, and edges with two equivalent Se(8)ZnCr3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Zn3Cr8FeSe16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.955
_cell_length_b   12.955
_cell_length_c   12.955
_cell_angle_alpha   33.551
_cell_angle_beta   33.551
_cell_angle_gamma   33.551
_symmetry_Int_Tables_number   1
_cell_volume   591.559
_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
  Zn  Zn0  1  0.188  0.188  0.188  1.0
  Zn  Zn1  1  0.813  0.813  0.813  1.0
  Zn  Zn2  1  0.313  0.313  0.313  1.0
  Cr  Cr3  1  1.000  1.000  1.000  1.0
  Cr  Cr4  1  0.500  0.500  0.500  1.0
  Cr  Cr5  1  0.750  0.250  0.250  1.0
  Cr  Cr6  1  0.250  0.750  0.750  1.0
  Cr  Cr7  1  0.250  0.750  0.250  1.0
  Cr  Cr8  1  0.750  0.250  0.750  1.0
  Cr  Cr9  1  0.250  0.250  0.750  1.0
  Cr  Cr10  1  0.750  0.750  0.250  1.0
  Fe  Fe11  1  0.687  0.687  0.687  1.0
  Se  Se12  1  0.120  0.120  0.120  1.0
  Se  Se13  1  0.621  0.621  0.621  1.0
  Se  Se14  1  0.353  0.888  0.888  1.0
  Se  Se15  1  0.849  0.391  0.391  1.0
  Se  Se16  1  0.888  0.353  0.888  1.0
  Se  Se17  1  0.391  0.849  0.391  1.0
  Se  Se18  1  0.888  0.888  0.353  1.0
  Se  Se19  1  0.391  0.391  0.849  1.0
  Se  Se20  1  0.380  0.380  0.380  1.0
  Se  Se21  1  0.880  0.880  0.880  1.0
  Se  Se22  1  0.151  0.609  0.609  1.0
  Se  Se23  1  0.651  0.109  0.109  1.0
  Se  Se24  1  0.609  0.151  0.609  1.0
  Se  Se25  1  0.109  0.651  0.109  1.0
  Se  Se26  1  0.609  0.609  0.151  1.0
  Se  Se27  1  0.109  0.109  0.651  1.0
[/CIF]
.
The compound described by Cr8FeZn3Se16 is Spinel-derived structured and crystallizes in the trigonal R3m space group. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three equivalent Se(3) and three equivalent Se(8) atoms to form CrSe6 octahedra that share corners with three equivalent Fe(1)Se4 tetrahedra, corners with three equivalent Zn(3)Se4 tetrahedra, edges with three equivalent Cr(3)Se6 octahedra, and edges with three equivalent Cr(4)Se6 octahedra. In the second Cr site, Cr(2) is bonded to three equivalent Se(4) and three equivalent Se(7) atoms to form CrSe6 octahedra that share corners with three equivalent Zn(1)Se4 tetrahedra, corners with three equivalent Zn(2)Se4 tetrahedra, edges with three equivalent Cr(3)Se6 octahedra, and edges with three equivalent Cr(4)Se6 octahedra. In the third Cr site, Cr(3) is bonded to one Se(1), one Se(5), two equivalent Se(3), and two equivalent Se(7) atoms to form CrSe6 octahedra that share  a cornercorner with one Zn(1)Se4 tetrahedra,  a cornercorner with one Zn(3)Se4 tetrahedra, corners with two equivalent Fe(1)Se4 tetrahedra, corners with two equivalent Zn(2)Se4 tetrahedra,  an edgeedge with one Cr(1)Se6 octahedra,  an edgeedge with one Cr(2)Se6 octahedra, and edges with four equivalent Cr(3)Se6 octahedra. In the fourth Cr site, Cr(4) is bonded to one Se(2), one Se(6), two equivalent Se(4), and two equivalent Se(8) atoms to form CrSe6 octahedra that share  a cornercorner with one Fe(1)Se4 tetrahedra,  a cornercorner with one Zn(2)Se4 tetrahedra, corners with two equivalent Zn(1)Se4 tetrahedra, corners with two equivalent Zn(3)Se4 tetrahedra,  an edgeedge with one Cr(1)Se6 octahedra,  an edgeedge with one Cr(2)Se6 octahedra, and edges with four equivalent Cr(4)Se6 octahedra. Fe(1) is bonded to one Se(2) and three equivalent Se(3) atoms to form FeSe4 tetrahedra that share corners with three equivalent Cr(1)Se6 octahedra, corners with three equivalent Cr(4)Se6 octahedra, and corners with six equivalent Cr(3)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one Se(1) and three equivalent Se(4) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Cr(2)Se6 octahedra, corners with three equivalent Cr(3)Se6 octahedra, and corners with six equivalent Cr(4)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Zn site, Zn(2) is bonded to one Se(6) and three equivalent Se(7) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Cr(2)Se6 octahedra, corners with three equivalent Cr(4)Se6 octahedra, and corners with six equivalent Cr(3)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the third Zn site, Zn(3) is bonded to one Se(5) and three equivalent Se(8) atoms to form ZnSe4 tetrahedra that share corners with three equivalent Cr(1)Se6 octahedra, corners with three equivalent Cr(3)Se6 octahedra, and corners with six equivalent Cr(4)Se6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Cr(3) and one Zn(1) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(4)ZnCr3 trigonal pyramids, corners with three equivalent Se(5)ZnCr3 trigonal pyramids, corners with six equivalent Se(7)ZnCr3 trigonal pyramids, and edges with three equivalent Se(3)Cr3Fe trigonal pyramids. In the second Se site, Se(2) is bonded to three equivalent Cr(4) and one Fe(1) atom to form distorted SeCr3Fe trigonal pyramids that share corners with three equivalent Se(3)Cr3Fe trigonal pyramids, corners with three equivalent Se(6)ZnCr3 trigonal pyramids, corners with six equivalent Se(8)ZnCr3 trigonal pyramids, and edges with three equivalent Se(4)ZnCr3 trigonal pyramids. In the third Se site, Se(3) is bonded to one Cr(1), two equivalent Cr(3), and one Fe(1) atom to form distorted SeCr3Fe trigonal pyramids that share  a cornercorner with one Se(2)Cr3Fe trigonal pyramid, corners with two equivalent Se(3)Cr3Fe trigonal pyramids, corners with two equivalent Se(5)ZnCr3 trigonal pyramids, corners with three equivalent Se(8)ZnCr3 trigonal pyramids, corners with four equivalent Se(7)ZnCr3 trigonal pyramids,  an edgeedge with one Se(1)ZnCr3 trigonal pyramid, and edges with two equivalent Se(3)Cr3Fe trigonal pyramids. In the fourth Se site, Se(4) is bonded to one Cr(2), two equivalent Cr(4), and one Zn(1) atom to form distorted SeZnCr3 trigonal pyramids that share  a cornercorner with one Se(1)ZnCr3 trigonal pyramid, corners with two equivalent Se(4)ZnCr3 trigonal pyramids, corners with two equivalent Se(6)ZnCr3 trigonal pyramids, corners with three equivalent Se(7)ZnCr3 trigonal pyramids, corners with four equivalent Se(8)ZnCr3 trigonal pyramids,  an edgeedge with one Se(2)Cr3Fe trigonal pyramid, and edges with two equivalent Se(4)ZnCr3 trigonal pyramids. In the fifth Se site, Se(5) is bonded to three equivalent Cr(3) and one Zn(3) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(1)ZnCr3 trigonal pyramids, corners with three equivalent Se(8)ZnCr3 trigonal pyramids, corners with six equivalent Se(3)Cr3Fe trigonal pyramids, and edges with three equivalent Se(7)ZnCr3 trigonal pyramids. In the sixth Se site, Se(6) is bonded to three equivalent Cr(4) and one Zn(2) atom to form distorted SeZnCr3 trigonal pyramids that share corners with three equivalent Se(2)Cr3Fe trigonal pyramids, corners with three equivalent Se(7)ZnCr3 trigonal pyramids, corners with six equivalent Se(4)ZnCr3 trigonal pyramids, and edges with three equivalent Se(8)ZnCr3 trigonal pyramids. In the seventh Se site, Se(7) is bonded to one Cr(2), two equivalent Cr(3), and one Zn(2) atom to form distorted SeZnCr3 trigonal pyramids that share  a cornercorner with one Se(6)ZnCr3 trigonal pyramid, corners with two equivalent Se(1)ZnCr3 trigonal pyramids, corners with two equivalent Se(7)ZnCr3 trigonal pyramids, corners with three equivalent Se(4)ZnCr3 trigonal pyramids, corners with four equivalent Se(3)Cr3Fe trigonal pyramids,  an edgeedge with one Se(5)ZnCr3 trigonal pyramid, and edges with two equivalent Se(7)ZnCr3 trigonal pyramids. In the eighth Se site, Se(8) is bonded to one Cr(1), two equivalent Cr(4), and one Zn(3) atom to form distorted SeZnCr3 trigonal pyramids that share  a cornercorner with one Se(5)ZnCr3 trigonal pyramid, corners with two equivalent Se(2)Cr3Fe trigonal pyramids, corners with two equivalent Se(8)ZnCr3 trigonal pyramids, corners with three equivalent Se(3)Cr3Fe trigonal pyramids, corners with four equivalent Se(4)ZnCr3 trigonal pyramids,  an edgeedge with one Se(6)ZnCr3 trigonal pyramid, and edges with two equivalent Se(8)ZnCr3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Zn3Cr8FeSe16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.955
_cell_length_b   12.955
_cell_length_c   12.955
_cell_angle_alpha   33.551
_cell_angle_beta   33.551
_cell_angle_gamma   33.551
_symmetry_Int_Tables_number   1
_cell_volume   591.559
_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
  Zn  Zn0  1  0.188  0.188  0.188  1.0
  Zn  Zn1  1  0.813  0.813  0.813  1.0
  Zn  Zn2  1  0.313  0.313  0.313  1.0
  Cr  Cr3  1  1.000  1.000  1.000  1.0
  Cr  Cr4  1  0.500  0.500  0.500  1.0
  Cr  Cr5  1  0.750  0.250  0.250  1.0
  Cr  Cr6  1  0.250  0.750  0.750  1.0
  Cr  Cr7  1  0.250  0.750  0.250  1.0
  Cr  Cr8  1  0.750  0.250  0.750  1.0
  Cr  Cr9  1  0.250  0.250  0.750  1.0
  Cr  Cr10  1  0.750  0.750  0.250  1.0
  Fe  Fe11  1  0.687  0.687  0.687  1.0
  Se  Se12  1  0.120  0.120  0.120  1.0
  Se  Se13  1  0.621  0.621  0.621  1.0
  Se  Se14  1  0.353  0.888  0.888  1.0
  Se  Se15  1  0.849  0.391  0.391  1.0
  Se  Se16  1  0.888  0.353  0.888  1.0
  Se  Se17  1  0.391  0.849  0.391  1.0
  Se  Se18  1  0.888  0.888  0.353  1.0
  Se  Se19  1  0.391  0.391  0.849  1.0
  Se  Se20  1  0.380  0.380  0.380  1.0
  Se  Se21  1  0.880  0.880  0.880  1.0
  Se  Se22  1  0.151  0.609  0.609  1.0
  Se  Se23  1  0.651  0.109  0.109  1.0
  Se  Se24  1  0.609  0.151  0.609  1.0
  Se  Se25  1  0.109  0.651  0.109  1.0
  Se  Se26  1  0.609  0.609  0.151  1.0
  Se  Se27  1  0.109  0.109  0.651  1.0
[/CIF]
.