The structure described by Mg(CuS)6 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 7-coordinate geometry to one Cu(3), three equivalent S(1), and three equivalent S(3) atoms. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one S(6) and three equivalent S(1) atoms to form corner-sharing CuS4 tetrahedra. In the second Cu site, Cu(2) is bonded to one S(5) and three equivalent S(2) atoms to form CuS4 tetrahedra that share corners with three equivalent S(4)Cu3S tetrahedra and corners with six equivalent Cu(2)S4 tetrahedra. In the third Cu site, Cu(3) is bonded in a 5-coordinate geometry to one Mg(1), one S(5), and three equivalent S(3) atoms. In the fourth Cu site, Cu(4) is bonded to one S(6) and three equivalent S(4) atoms to form CuS4 tetrahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with three equivalent S(2)Cu3S tetrahedra, and corners with six equivalent Cu(4)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded in a trigonal planar geometry to three equivalent S(6) atoms. In the sixth Cu site, Cu(6) is bonded in a trigonal planar geometry to three equivalent S(5) atoms. There are six inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Mg(1) and three equivalent Cu(1) atoms to form SMg3Cu3 octahedra that share corners with three equivalent S(6)Cu5 trigonal bipyramids and edges with six equivalent S(1)Mg3Cu3 octahedra. In the second S site, S(2) is bonded to three equivalent Cu(2) and one S(4) atom to form distorted SCu3S tetrahedra that share corners with three equivalent Cu(4)S4 tetrahedra, corners with six equivalent S(2)Cu3S tetrahedra, and corners with three equivalent S(5)Cu5 trigonal bipyramids. In the third S site, S(3) is bonded in a 6-coordinate geometry to three equivalent Mg(1) and three equivalent Cu(3) atoms. In the fourth S site, S(4) is bonded to three equivalent Cu(4) and one S(2) atom to form distorted SCu3S tetrahedra that share corners with three equivalent Cu(2)S4 tetrahedra, corners with six equivalent S(4)Cu3S tetrahedra, and corners with three equivalent S(6)Cu5 trigonal bipyramids. In the fifth S site, S(5) is bonded to one Cu(2), one Cu(3), and three equivalent Cu(6) atoms to form SCu5 trigonal bipyramids that share corners with three equivalent S(2)Cu3S tetrahedra and corners with six equivalent S(5)Cu5 trigonal bipyramids. In the sixth S site, S(6) is bonded to one Cu(1), one Cu(4), and three equivalent Cu(5) atoms to form SCu5 trigonal bipyramids that share corners with three equivalent S(1)Mg3Cu3 octahedra, corners with three equivalent S(4)Cu3S tetrahedra, and corners with six equivalent S(6)Cu5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 67°. is represented by the CIF file [CIF]
data_Mg(CuS)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.758
_cell_length_b   3.756
_cell_length_c   18.023
_cell_angle_alpha   89.577
_cell_angle_beta   90.000
_cell_angle_gamma   120.012
_symmetry_Int_Tables_number   1
_cell_volume   220.296
_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  0.663  0.326  0.491  1.0
  Cu  Cu1  1  0.331  0.661  0.355  1.0
  Cu  Cu2  1  0.668  0.335  0.901  1.0
  Cu  Cu3  1  0.669  0.338  0.641  1.0
  Cu  Cu4  1  0.332  0.664  0.097  1.0
  Cu  Cu5  1  0.667  0.333  0.241  1.0
  Cu  Cu6  1  0.333  0.667  0.753  1.0
  S  S7  1  0.995  0.990  0.406  1.0
  S  S8  1  0.000  0.001  0.940  1.0
  S  S9  1  0.004  0.007  0.591  1.0
  S  S10  1  0.999  0.999  0.057  1.0
  S  S11  1  0.666  0.333  0.772  1.0
  S  S12  1  0.333  0.667  0.226  1.0
[/CIF]
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The structure described by Mg(CuS)6 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 7-coordinate geometry to one Cu(3), three equivalent S(1), and three equivalent S(3) atoms. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one S(6) and three equivalent S(1) atoms to form corner-sharing CuS4 tetrahedra. In the second Cu site, Cu(2) is bonded to one S(5) and three equivalent S(2) atoms to form CuS4 tetrahedra that share corners with three equivalent S(4)Cu3S tetrahedra and corners with six equivalent Cu(2)S4 tetrahedra. In the third Cu site, Cu(3) is bonded in a 5-coordinate geometry to one Mg(1), one S(5), and three equivalent S(3) atoms. In the fourth Cu site, Cu(4) is bonded to one S(6) and three equivalent S(4) atoms to form CuS4 tetrahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with three equivalent S(2)Cu3S tetrahedra, and corners with six equivalent Cu(4)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded in a trigonal planar geometry to three equivalent S(6) atoms. In the sixth Cu site, Cu(6) is bonded in a trigonal planar geometry to three equivalent S(5) atoms. There are six inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Mg(1) and three equivalent Cu(1) atoms to form SMg3Cu3 octahedra that share corners with three equivalent S(6)Cu5 trigonal bipyramids and edges with six equivalent S(1)Mg3Cu3 octahedra. In the second S site, S(2) is bonded to three equivalent Cu(2) and one S(4) atom to form distorted SCu3S tetrahedra that share corners with three equivalent Cu(4)S4 tetrahedra, corners with six equivalent S(2)Cu3S tetrahedra, and corners with three equivalent S(5)Cu5 trigonal bipyramids. In the third S site, S(3) is bonded in a 6-coordinate geometry to three equivalent Mg(1) and three equivalent Cu(3) atoms. In the fourth S site, S(4) is bonded to three equivalent Cu(4) and one S(2) atom to form distorted SCu3S tetrahedra that share corners with three equivalent Cu(2)S4 tetrahedra, corners with six equivalent S(4)Cu3S tetrahedra, and corners with three equivalent S(6)Cu5 trigonal bipyramids. In the fifth S site, S(5) is bonded to one Cu(2), one Cu(3), and three equivalent Cu(6) atoms to form SCu5 trigonal bipyramids that share corners with three equivalent S(2)Cu3S tetrahedra and corners with six equivalent S(5)Cu5 trigonal bipyramids. In the sixth S site, S(6) is bonded to one Cu(1), one Cu(4), and three equivalent Cu(5) atoms to form SCu5 trigonal bipyramids that share corners with three equivalent S(1)Mg3Cu3 octahedra, corners with three equivalent S(4)Cu3S tetrahedra, and corners with six equivalent S(6)Cu5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 67°. is represented by the CIF file [CIF]
data_Mg(CuS)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.758
_cell_length_b   3.756
_cell_length_c   18.023
_cell_angle_alpha   89.577
_cell_angle_beta   90.000
_cell_angle_gamma   120.012
_symmetry_Int_Tables_number   1
_cell_volume   220.296
_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  0.663  0.326  0.491  1.0
  Cu  Cu1  1  0.331  0.661  0.355  1.0
  Cu  Cu2  1  0.668  0.335  0.901  1.0
  Cu  Cu3  1  0.669  0.338  0.641  1.0
  Cu  Cu4  1  0.332  0.664  0.097  1.0
  Cu  Cu5  1  0.667  0.333  0.241  1.0
  Cu  Cu6  1  0.333  0.667  0.753  1.0
  S  S7  1  0.995  0.990  0.406  1.0
  S  S8  1  0.000  0.001  0.940  1.0
  S  S9  1  0.004  0.007  0.591  1.0
  S  S10  1  0.999  0.999  0.057  1.0
  S  S11  1  0.666  0.333  0.772  1.0
  S  S12  1  0.333  0.667  0.226  1.0
[/CIF]
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