The crystal structure described by Cu5FeS4 crystallizes in the trigonal R3m space group. Fe(1) is bonded to one S(3) and three equivalent S(1) atoms to form FeS4 tetrahedra that share corners with three equivalent Cu(3)S4 tetrahedra, corners with three equivalent Cu(4)S4 tetrahedra, corners with three equivalent Cu(5)S4 tetrahedra, corners with six equivalent Fe(1)S4 tetrahedra, and edges with three equivalent Cu(3)S4 tetrahedra. There are five inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one S(4) and three equivalent S(2) atoms to form a mixture of edge and corner-sharing CuS4 tetrahedra. In the second Cu site, Cu(2) is bonded in a trigonal planar geometry to three equivalent S(4) atoms. In the third Cu site, Cu(3) is bonded to one S(2) and three equivalent S(1) atoms to form distorted CuS4 tetrahedra that share corners with three equivalent Fe(1)S4 tetrahedra, corners with three equivalent Cu(1)S4 tetrahedra, corners with six equivalent Cu(3)S4 tetrahedra, edges with three equivalent Fe(1)S4 tetrahedra, and edges with three equivalent Cu(5)S4 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one S(4) and three equivalent S(3) atoms to form CuS4 tetrahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with three equivalent Fe(1)S4 tetrahedra, and corners with six equivalent Cu(4)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one S(1) and three equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with three equivalent Fe(1)S4 tetrahedra, corners with three equivalent Cu(1)S4 tetrahedra, corners with six equivalent Cu(5)S4 tetrahedra, edges with three equivalent Cu(1)S4 tetrahedra, and edges with three equivalent Cu(3)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to three equivalent Fe(1), one Cu(5), and three equivalent Cu(3) atoms. In the second S site, S(2) is bonded in a 7-coordinate geometry to one Cu(3), three equivalent Cu(1), and three equivalent Cu(5) atoms. In the third S site, S(3) is bonded to one Fe(1) and three equivalent Cu(4) atoms to form SFeCu3 tetrahedra that share corners with six equivalent S(3)FeCu3 tetrahedra and corners with three equivalent S(4)Cu5 trigonal bipyramids. In the fourth S site, S(4) is bonded to one Cu(1), one Cu(4), and three equivalent Cu(2) atoms to form SCu5 trigonal bipyramids that share corners with three equivalent S(3)FeCu3 tetrahedra and corners with six equivalent S(4)Cu5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeCu5S4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.796
_cell_length_b   12.796
_cell_length_c   12.796
_cell_angle_alpha   17.271
_cell_angle_beta   17.271
_cell_angle_gamma   17.271
_symmetry_Int_Tables_number   1
_cell_volume   161.160
_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
  Fe  Fe0  1  0.305  0.305  0.305  1.0
  Cu  Cu1  1  0.441  0.441  0.441  1.0
  Cu  Cu2  1  0.831  0.831  0.831  1.0
  Cu  Cu3  1  0.686  0.686  0.686  1.0
  Cu  Cu4  1  0.566  0.566  0.566  1.0
  Cu  Cu5  1  0.060  0.060  0.060  1.0
  S  S6  1  0.993  0.993  0.993  1.0
  S  S7  1  0.747  0.747  0.747  1.0
  S  S8  1  0.247  0.247  0.247  1.0
  S  S9  1  0.501  0.501  0.501  1.0
[/CIF]
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The crystal structure described by Cu5FeS4 crystallizes in the trigonal R3m space group. Fe(1) is bonded to one S(3) and three equivalent S(1) atoms to form FeS4 tetrahedra that share corners with three equivalent Cu(3)S4 tetrahedra, corners with three equivalent Cu(4)S4 tetrahedra, corners with three equivalent Cu(5)S4 tetrahedra, corners with six equivalent Fe(1)S4 tetrahedra, and edges with three equivalent Cu(3)S4 tetrahedra. There are five inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one S(4) and three equivalent S(2) atoms to form a mixture of edge and corner-sharing CuS4 tetrahedra. In the second Cu site, Cu(2) is bonded in a trigonal planar geometry to three equivalent S(4) atoms. In the third Cu site, Cu(3) is bonded to one S(2) and three equivalent S(1) atoms to form distorted CuS4 tetrahedra that share corners with three equivalent Fe(1)S4 tetrahedra, corners with three equivalent Cu(1)S4 tetrahedra, corners with six equivalent Cu(3)S4 tetrahedra, edges with three equivalent Fe(1)S4 tetrahedra, and edges with three equivalent Cu(5)S4 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one S(4) and three equivalent S(3) atoms to form CuS4 tetrahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with three equivalent Fe(1)S4 tetrahedra, and corners with six equivalent Cu(4)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one S(1) and three equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with three equivalent Fe(1)S4 tetrahedra, corners with three equivalent Cu(1)S4 tetrahedra, corners with six equivalent Cu(5)S4 tetrahedra, edges with three equivalent Cu(1)S4 tetrahedra, and edges with three equivalent Cu(3)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to three equivalent Fe(1), one Cu(5), and three equivalent Cu(3) atoms. In the second S site, S(2) is bonded in a 7-coordinate geometry to one Cu(3), three equivalent Cu(1), and three equivalent Cu(5) atoms. In the third S site, S(3) is bonded to one Fe(1) and three equivalent Cu(4) atoms to form SFeCu3 tetrahedra that share corners with six equivalent S(3)FeCu3 tetrahedra and corners with three equivalent S(4)Cu5 trigonal bipyramids. In the fourth S site, S(4) is bonded to one Cu(1), one Cu(4), and three equivalent Cu(2) atoms to form SCu5 trigonal bipyramids that share corners with three equivalent S(3)FeCu3 tetrahedra and corners with six equivalent S(4)Cu5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeCu5S4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.796
_cell_length_b   12.796
_cell_length_c   12.796
_cell_angle_alpha   17.271
_cell_angle_beta   17.271
_cell_angle_gamma   17.271
_symmetry_Int_Tables_number   1
_cell_volume   161.160
_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
  Fe  Fe0  1  0.305  0.305  0.305  1.0
  Cu  Cu1  1  0.441  0.441  0.441  1.0
  Cu  Cu2  1  0.831  0.831  0.831  1.0
  Cu  Cu3  1  0.686  0.686  0.686  1.0
  Cu  Cu4  1  0.566  0.566  0.566  1.0
  Cu  Cu5  1  0.060  0.060  0.060  1.0
  S  S6  1  0.993  0.993  0.993  1.0
  S  S7  1  0.747  0.747  0.747  1.0
  S  S8  1  0.247  0.247  0.247  1.0
  S  S9  1  0.501  0.501  0.501  1.0
[/CIF]
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