The crystal structure described by MgFeCu5S4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one S(1) and three equivalent S(3) atoms to form distorted MgS4 tetrahedra that share corners with three equivalent Cu(4)S4 tetrahedra, corners with six equivalent Mg(1)S4 tetrahedra, and edges with three equivalent Cu(4)S4 tetrahedra. Fe(1) is bonded in a trigonal planar geometry to three equivalent S(1) atoms. 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 distorted 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 in a 4-coordinate geometry to one S(2) and three equivalent S(1) atoms. In the fourth Cu site, Cu(4) is bonded to one S(4) and three equivalent S(3) atoms to form distorted CuS4 tetrahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with three equivalent Mg(1)S4 tetrahedra, corners with six equivalent Cu(4)S4 tetrahedra, and edges with three equivalent Mg(1)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded in a trigonal non-coplanar geometry to three equivalent S(2) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to one Mg(1), three equivalent Fe(1), 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 three equivalent Mg(1) and three equivalent Cu(4) atoms to form distorted SMg3Cu3 octahedra that share corners with three equivalent S(4)Cu5 trigonal bipyramids and edges with six equivalent S(3)Mg3Cu3 octahedra. 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)Mg3Cu3 octahedra and corners with six equivalent S(4)Cu5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 64-66°. is represented by the CIF file [CIF]
data_MgFeCu5S4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.844
_cell_length_b   3.837
_cell_length_c   14.110
_cell_angle_alpha   97.737
_cell_angle_beta   90.000
_cell_angle_gamma   120.059
_symmetry_Int_Tables_number   1
_cell_volume   177.920
_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
  Mg  Mg0  1  0.067  0.133  0.199  1.0
  Fe  Fe1  1  0.676  0.353  0.029  1.0
  Cu  Cu2  1  0.560  0.120  0.684  1.0
  Cu  Cu3  1  0.171  0.341  0.508  1.0
  Cu  Cu4  1  0.306  0.612  0.920  1.0
  Cu  Cu5  1  0.451  0.902  0.358  1.0
  Cu  Cu6  1  0.933  0.865  0.802  1.0
  S  S7  1  0.007  0.014  0.020  1.0
  S  S8  1  0.252  0.505  0.758  1.0
  S  S9  1  0.761  0.522  0.284  1.0
  S  S10  1  0.509  0.018  0.521  1.0
[/CIF]
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The crystal structure described by MgFeCu5S4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one S(1) and three equivalent S(3) atoms to form distorted MgS4 tetrahedra that share corners with three equivalent Cu(4)S4 tetrahedra, corners with six equivalent Mg(1)S4 tetrahedra, and edges with three equivalent Cu(4)S4 tetrahedra. Fe(1) is bonded in a trigonal planar geometry to three equivalent S(1) atoms. 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 distorted 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 in a 4-coordinate geometry to one S(2) and three equivalent S(1) atoms. In the fourth Cu site, Cu(4) is bonded to one S(4) and three equivalent S(3) atoms to form distorted CuS4 tetrahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with three equivalent Mg(1)S4 tetrahedra, corners with six equivalent Cu(4)S4 tetrahedra, and edges with three equivalent Mg(1)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded in a trigonal non-coplanar geometry to three equivalent S(2) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to one Mg(1), three equivalent Fe(1), 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 three equivalent Mg(1) and three equivalent Cu(4) atoms to form distorted SMg3Cu3 octahedra that share corners with three equivalent S(4)Cu5 trigonal bipyramids and edges with six equivalent S(3)Mg3Cu3 octahedra. 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)Mg3Cu3 octahedra and corners with six equivalent S(4)Cu5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 64-66°. is represented by the CIF file [CIF]
data_MgFeCu5S4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.844
_cell_length_b   3.837
_cell_length_c   14.110
_cell_angle_alpha   97.737
_cell_angle_beta   90.000
_cell_angle_gamma   120.059
_symmetry_Int_Tables_number   1
_cell_volume   177.920
_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
  Mg  Mg0  1  0.067  0.133  0.199  1.0
  Fe  Fe1  1  0.676  0.353  0.029  1.0
  Cu  Cu2  1  0.560  0.120  0.684  1.0
  Cu  Cu3  1  0.171  0.341  0.508  1.0
  Cu  Cu4  1  0.306  0.612  0.920  1.0
  Cu  Cu5  1  0.451  0.902  0.358  1.0
  Cu  Cu6  1  0.933  0.865  0.802  1.0
  S  S7  1  0.007  0.014  0.020  1.0
  S  S8  1  0.252  0.505  0.758  1.0
  S  S9  1  0.761  0.522  0.284  1.0
  S  S10  1  0.509  0.018  0.521  1.0
[/CIF]
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