The material structure described by TaNb(Cu3S4)2 is Sulvanite-derived structured and crystallizes in the tetragonal P-4m2 space group. Ta(1) is bonded to four equivalent S(1) atoms to form TaS4 tetrahedra that share edges with two equivalent Cu(3)S4 tetrahedra and edges with four equivalent Cu(1)S4 tetrahedra. Nb(1) is bonded to four equivalent S(2) atoms to form NbS4 tetrahedra that share edges with two equivalent Cu(2)S4 tetrahedra and edges with four equivalent Cu(1)S4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with two equivalent Cu(2)S4 tetrahedra, corners with two equivalent Cu(3)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra,  an edgeedge with one Ta(1)S4 tetrahedra, and  an edgeedge with one Nb(1)S4 tetrahedra. In the second Cu site, Cu(2) is bonded to four equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with eight equivalent Cu(1)S4 tetrahedra and edges with two equivalent Nb(1)S4 tetrahedra. In the third Cu site, Cu(3) is bonded to four equivalent S(1) atoms to form distorted CuS4 tetrahedra that share corners with eight equivalent Cu(1)S4 tetrahedra and edges with two equivalent Ta(1)S4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Ta(1), one Cu(3), and two equivalent Cu(1) atoms to form distorted STaCu3 tetrahedra that share corners with two equivalent S(1)TaCu3 tetrahedra, corners with four equivalent S(2)NbCu3 tetrahedra, and edges with three equivalent S(1)TaCu3 tetrahedra. In the second S site, S(2) is bonded to one Nb(1), one Cu(2), and two equivalent Cu(1) atoms to form SNbCu3 tetrahedra that share corners with two equivalent S(2)NbCu3 tetrahedra, corners with four equivalent S(1)TaCu3 tetrahedra, and edges with three equivalent S(2)NbCu3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TaNb(Cu3S4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.834
_cell_length_b   7.834
_cell_length_c   5.540
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   340.046
_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
  Ta  Ta0  1  0.500  0.500  0.000  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.250  0.750  0.000  1.0
  Cu  Cu3  1  0.750  0.250  0.000  1.0
  Cu  Cu4  1  0.250  0.250  0.000  1.0
  Cu  Cu5  1  0.750  0.750  0.000  1.0
  Cu  Cu6  1  0.000  0.000  0.500  1.0
  Cu  Cu7  1  0.500  0.500  0.500  1.0
  S  S8  1  0.500  0.259  0.759  1.0
  S  S9  1  0.000  0.758  0.758  1.0
  S  S10  1  0.500  0.741  0.759  1.0
  S  S11  1  0.000  0.242  0.758  1.0
  S  S12  1  0.758  0.000  0.242  1.0
  S  S13  1  0.259  0.500  0.241  1.0
  S  S14  1  0.242  0.000  0.242  1.0
  S  S15  1  0.741  0.500  0.241  1.0
[/CIF]
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The material structure described by TaNb(Cu3S4)2 is Sulvanite-derived structured and crystallizes in the tetragonal P-4m2 space group. Ta(1) is bonded to four equivalent S(1) atoms to form TaS4 tetrahedra that share edges with two equivalent Cu(3)S4 tetrahedra and edges with four equivalent Cu(1)S4 tetrahedra. Nb(1) is bonded to four equivalent S(2) atoms to form NbS4 tetrahedra that share edges with two equivalent Cu(2)S4 tetrahedra and edges with four equivalent Cu(1)S4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with two equivalent Cu(2)S4 tetrahedra, corners with two equivalent Cu(3)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra,  an edgeedge with one Ta(1)S4 tetrahedra, and  an edgeedge with one Nb(1)S4 tetrahedra. In the second Cu site, Cu(2) is bonded to four equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with eight equivalent Cu(1)S4 tetrahedra and edges with two equivalent Nb(1)S4 tetrahedra. In the third Cu site, Cu(3) is bonded to four equivalent S(1) atoms to form distorted CuS4 tetrahedra that share corners with eight equivalent Cu(1)S4 tetrahedra and edges with two equivalent Ta(1)S4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Ta(1), one Cu(3), and two equivalent Cu(1) atoms to form distorted STaCu3 tetrahedra that share corners with two equivalent S(1)TaCu3 tetrahedra, corners with four equivalent S(2)NbCu3 tetrahedra, and edges with three equivalent S(1)TaCu3 tetrahedra. In the second S site, S(2) is bonded to one Nb(1), one Cu(2), and two equivalent Cu(1) atoms to form SNbCu3 tetrahedra that share corners with two equivalent S(2)NbCu3 tetrahedra, corners with four equivalent S(1)TaCu3 tetrahedra, and edges with three equivalent S(2)NbCu3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TaNb(Cu3S4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.834
_cell_length_b   7.834
_cell_length_c   5.540
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   340.046
_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
  Ta  Ta0  1  0.500  0.500  0.000  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.250  0.750  0.000  1.0
  Cu  Cu3  1  0.750  0.250  0.000  1.0
  Cu  Cu4  1  0.250  0.250  0.000  1.0
  Cu  Cu5  1  0.750  0.750  0.000  1.0
  Cu  Cu6  1  0.000  0.000  0.500  1.0
  Cu  Cu7  1  0.500  0.500  0.500  1.0
  S  S8  1  0.500  0.259  0.759  1.0
  S  S9  1  0.000  0.758  0.758  1.0
  S  S10  1  0.500  0.741  0.759  1.0
  S  S11  1  0.000  0.242  0.758  1.0
  S  S12  1  0.758  0.000  0.242  1.0
  S  S13  1  0.259  0.500  0.241  1.0
  S  S14  1  0.242  0.000  0.242  1.0
  S  S15  1  0.741  0.500  0.241  1.0
[/CIF]
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