The crystal structure described by Cr8Fe3CuS16 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 S(4), two equivalent S(3), and three equivalent S(1) atoms to form CrS6 octahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with two equivalent Fe(1)S4 tetrahedra, corners with three equivalent Fe(2)S4 tetrahedra, edges with two equivalent Cr(2)S6 octahedra, and edges with four equivalent Cr(1)S6 octahedra. In the second Cr site, Cr(2) is bonded to one S(3), two equivalent S(4), and three equivalent S(2) atoms to form CrS6 octahedra that share  a cornercorner with one Fe(1)S4 tetrahedra, corners with two equivalent Cu(1)S4 tetrahedra, corners with three equivalent Fe(2)S4 tetrahedra, edges with two equivalent Cr(1)S6 octahedra, and edges with four equivalent Cr(2)S6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent S(3) atoms to form FeS4 tetrahedra that share corners with four equivalent Cr(2)S6 octahedra and corners with eight equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Fe site, Fe(2) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form FeS4 tetrahedra that share corners with six equivalent Cr(1)S6 octahedra and corners with six equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 55-56°. Cu(1) is bonded to four equivalent S(4) atoms to form CuS4 tetrahedra that share corners with four equivalent Cr(1)S6 octahedra and corners with eight equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to three equivalent Cr(1) and one Fe(2) atom. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to three equivalent Cr(2) and one Fe(2) atom. In the third S site, S(3) is bonded in a distorted rectangular see-saw-like geometry to one Cr(2), two equivalent Cr(1), and one Fe(1) atom. In the fourth S site, S(4) is bonded to one Cr(1), two equivalent Cr(2), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SCr3Cu trigonal pyramids. is represented by the CIF file [CIF]
data_Cr8Fe3CuS16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.912
_cell_length_b   9.749
_cell_length_c   6.912
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   465.749
_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  0.751  0.249  1.0
  Cr  Cr1  1  0.750  0.250  0.750  1.0
  Cr  Cr2  1  0.750  0.250  0.250  1.0
  Cr  Cr3  1  0.250  0.751  0.751  1.0
  Cr  Cr4  1  0.499  0.499  0.000  1.0
  Cr  Cr5  1  1.000  0.000  0.500  1.0
  Cr  Cr6  1  0.001  0.499  0.000  1.0
  Cr  Cr7  1  0.500  0.000  0.500  1.0
  Fe  Fe8  1  0.750  0.625  0.500  1.0
  Fe  Fe9  1  0.750  0.876  0.000  1.0
  Fe  Fe10  1  0.250  0.374  0.500  1.0
  Cu  Cu11  1  0.250  0.125  0.000  1.0
  S  S12  1  0.250  0.502  0.758  1.0
  S  S13  1  0.750  0.004  0.256  1.0
  S  S14  1  0.250  0.502  0.242  1.0
  S  S15  1  0.750  0.004  0.744  1.0
  S  S16  1  0.008  0.748  0.000  1.0
  S  S17  1  0.506  0.246  0.500  1.0
  S  S18  1  0.492  0.748  0.000  1.0
  S  S19  1  0.994  0.246  0.500  1.0
  S  S20  1  0.750  0.494  0.235  1.0
  S  S21  1  0.250  0.991  0.732  1.0
  S  S22  1  0.750  0.494  0.765  1.0
  S  S23  1  0.250  0.991  0.268  1.0
  S  S24  1  0.982  0.259  0.000  1.0
  S  S25  1  0.485  0.756  0.500  1.0
  S  S26  1  0.518  0.259  0.000  1.0
  S  S27  1  0.015  0.756  0.500  1.0
[/CIF]
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The crystal structure described by Cr8Fe3CuS16 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 S(4), two equivalent S(3), and three equivalent S(1) atoms to form CrS6 octahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with two equivalent Fe(1)S4 tetrahedra, corners with three equivalent Fe(2)S4 tetrahedra, edges with two equivalent Cr(2)S6 octahedra, and edges with four equivalent Cr(1)S6 octahedra. In the second Cr site, Cr(2) is bonded to one S(3), two equivalent S(4), and three equivalent S(2) atoms to form CrS6 octahedra that share  a cornercorner with one Fe(1)S4 tetrahedra, corners with two equivalent Cu(1)S4 tetrahedra, corners with three equivalent Fe(2)S4 tetrahedra, edges with two equivalent Cr(1)S6 octahedra, and edges with four equivalent Cr(2)S6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent S(3) atoms to form FeS4 tetrahedra that share corners with four equivalent Cr(2)S6 octahedra and corners with eight equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Fe site, Fe(2) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form FeS4 tetrahedra that share corners with six equivalent Cr(1)S6 octahedra and corners with six equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 55-56°. Cu(1) is bonded to four equivalent S(4) atoms to form CuS4 tetrahedra that share corners with four equivalent Cr(1)S6 octahedra and corners with eight equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to three equivalent Cr(1) and one Fe(2) atom. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to three equivalent Cr(2) and one Fe(2) atom. In the third S site, S(3) is bonded in a distorted rectangular see-saw-like geometry to one Cr(2), two equivalent Cr(1), and one Fe(1) atom. In the fourth S site, S(4) is bonded to one Cr(1), two equivalent Cr(2), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SCr3Cu trigonal pyramids. is represented by the CIF file [CIF]
data_Cr8Fe3CuS16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.912
_cell_length_b   9.749
_cell_length_c   6.912
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   465.749
_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  0.751  0.249  1.0
  Cr  Cr1  1  0.750  0.250  0.750  1.0
  Cr  Cr2  1  0.750  0.250  0.250  1.0
  Cr  Cr3  1  0.250  0.751  0.751  1.0
  Cr  Cr4  1  0.499  0.499  0.000  1.0
  Cr  Cr5  1  1.000  0.000  0.500  1.0
  Cr  Cr6  1  0.001  0.499  0.000  1.0
  Cr  Cr7  1  0.500  0.000  0.500  1.0
  Fe  Fe8  1  0.750  0.625  0.500  1.0
  Fe  Fe9  1  0.750  0.876  0.000  1.0
  Fe  Fe10  1  0.250  0.374  0.500  1.0
  Cu  Cu11  1  0.250  0.125  0.000  1.0
  S  S12  1  0.250  0.502  0.758  1.0
  S  S13  1  0.750  0.004  0.256  1.0
  S  S14  1  0.250  0.502  0.242  1.0
  S  S15  1  0.750  0.004  0.744  1.0
  S  S16  1  0.008  0.748  0.000  1.0
  S  S17  1  0.506  0.246  0.500  1.0
  S  S18  1  0.492  0.748  0.000  1.0
  S  S19  1  0.994  0.246  0.500  1.0
  S  S20  1  0.750  0.494  0.235  1.0
  S  S21  1  0.250  0.991  0.732  1.0
  S  S22  1  0.750  0.494  0.765  1.0
  S  S23  1  0.250  0.991  0.268  1.0
  S  S24  1  0.982  0.259  0.000  1.0
  S  S25  1  0.485  0.756  0.500  1.0
  S  S26  1  0.518  0.259  0.000  1.0
  S  S27  1  0.015  0.756  0.500  1.0
[/CIF]
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