The compound described by MgNbCu3S4 crystallizes in the tetragonal P-42m space group. Mg(1) is bonded to four equivalent S(1) atoms to form distorted MgS4 tetrahedra that share corners with four equivalent Nb(1)Cu2S4 tetrahedra and edges with four equivalent Cu(1)S4 tetrahedra. Nb(1) is bonded to two equivalent Cu(2) and four equivalent S(1) atoms to form distorted NbCu2S4 tetrahedra that share corners with two equivalent Nb(1)Cu2S4 tetrahedra, corners with four equivalent Mg(1)S4 tetrahedra, and edges with four equivalent Cu(1)S4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent S(1) atoms to form distorted CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, edges with two equivalent Mg(1)S4 tetrahedra, and edges with two equivalent Nb(1)Cu2S4 tetrahedra. In the second Cu site, Cu(2) is bonded in a 6-coordinate geometry to two equivalent Nb(1) and four equivalent S(1) atoms. S(1) is bonded in a 5-coordinate geometry to one Mg(1), one Nb(1), one Cu(2), and two equivalent Cu(1) atoms. is represented by the CIF card [CIF]
data_MgNbCu3S4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.359
_cell_length_b   5.897
_cell_length_c   5.897
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   186.347
_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  0.000  0.500  0.500  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.000  0.000  0.500  1.0
  Cu  Cu3  1  0.000  0.500  0.000  1.0
  Cu  Cu4  1  0.500  0.000  0.000  1.0
  S  S5  1  0.766  0.755  0.245  1.0
  S  S6  1  0.766  0.245  0.755  1.0
  S  S7  1  0.234  0.755  0.755  1.0
  S  S8  1  0.234  0.245  0.245  1.0
[/CIF]
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The compound described by MgNbCu3S4 crystallizes in the tetragonal P-42m space group. Mg(1) is bonded to four equivalent S(1) atoms to form distorted MgS4 tetrahedra that share corners with four equivalent Nb(1)Cu2S4 tetrahedra and edges with four equivalent Cu(1)S4 tetrahedra. Nb(1) is bonded to two equivalent Cu(2) and four equivalent S(1) atoms to form distorted NbCu2S4 tetrahedra that share corners with two equivalent Nb(1)Cu2S4 tetrahedra, corners with four equivalent Mg(1)S4 tetrahedra, and edges with four equivalent Cu(1)S4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent S(1) atoms to form distorted CuS4 tetrahedra that share corners with four equivalent Cu(1)S4 tetrahedra, edges with two equivalent Mg(1)S4 tetrahedra, and edges with two equivalent Nb(1)Cu2S4 tetrahedra. In the second Cu site, Cu(2) is bonded in a 6-coordinate geometry to two equivalent Nb(1) and four equivalent S(1) atoms. S(1) is bonded in a 5-coordinate geometry to one Mg(1), one Nb(1), one Cu(2), and two equivalent Cu(1) atoms. is represented by the CIF card [CIF]
data_MgNbCu3S4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.359
_cell_length_b   5.897
_cell_length_c   5.897
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   186.347
_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  0.000  0.500  0.500  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.000  0.000  0.500  1.0
  Cu  Cu3  1  0.000  0.500  0.000  1.0
  Cu  Cu4  1  0.500  0.000  0.000  1.0
  S  S5  1  0.766  0.755  0.245  1.0
  S  S6  1  0.766  0.245  0.755  1.0
  S  S7  1  0.234  0.755  0.755  1.0
  S  S8  1  0.234  0.245  0.245  1.0
[/CIF]
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