The compound described by MgCu4(AsS)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 2-coordinate geometry to two equivalent Cu(3), one As(3), two equivalent As(2), one S(1), and two equivalent S(4) atoms. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one As(2), one S(3), and two equivalent S(2) atoms to form corner-sharing CuAsS3 tetrahedra. In the second Cu site, Cu(2) is bonded to one As(1), one S(2), and two equivalent S(3) atoms to form corner-sharing CuAsS3 tetrahedra. In the third Cu site, Cu(3) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one As(3), one S(1), and two equivalent S(4) atoms. In the fourth Cu site, Cu(4) is bonded to one As(4), one S(4), and two equivalent S(1) atoms to form distorted CuAsS3 tetrahedra that share  a cornercorner with one S(3)Cu3As tetrahedra, corners with two equivalent Cu(4)AsS3 tetrahedra, and corners with four equivalent As(1)CuAs2S tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded to one Cu(2), two equivalent As(4), and one S(1) atom to form distorted AsCuAs2S tetrahedra that share  a cornercorner with one S(2)Cu3As tetrahedra, corners with two equivalent As(1)CuAs2S tetrahedra, corners with four equivalent Cu(4)AsS3 tetrahedra, and corners with four equivalent S(3)Cu3As tetrahedra. In the second As site, As(2) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(1), and two equivalent As(3) atoms. In the third As site, As(3) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(3), two equivalent As(2), and one S(2) atom. In the fourth As site, As(4) is bonded in a 4-coordinate geometry to one Cu(4), two equivalent As(1), and one S(3) atom. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(3), two equivalent Cu(4), and one As(1) atom. In the second S site, S(2) is bonded to one Cu(2), two equivalent Cu(1), and one As(3) atom to form SCu3As tetrahedra that share  a cornercorner with one As(1)CuAs2S tetrahedra, corners with two equivalent S(2)Cu3As tetrahedra, and corners with four equivalent S(3)Cu3As tetrahedra. In the third S site, S(3) is bonded to one Cu(1), two equivalent Cu(2), and one As(4) atom to form SCu3As tetrahedra that share  a cornercorner with one Cu(4)AsS3 tetrahedra, corners with two equivalent S(3)Cu3As tetrahedra, corners with four equivalent As(1)CuAs2S tetrahedra, and corners with four equivalent S(2)Cu3As tetrahedra. In the fourth S site, S(4) is bonded to two equivalent Mg(1), one Cu(4), and two equivalent Cu(3) atoms to form distorted edge-sharing SMg2Cu3 square pyramids. is represented by the CIF card [CIF]
data_MgCu4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.730
_cell_length_b   5.672
_cell_length_c   12.262
_cell_angle_alpha   84.278
_cell_angle_beta   89.122
_cell_angle_gamma   89.417
_symmetry_Int_Tables_number   1
_cell_volume   258.074
_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  0.797  0.174  0.642  1.0
  Cu  Cu1  1  0.276  0.375  0.309  1.0
  Cu  Cu2  1  0.780  0.897  0.174  1.0
  Cu  Cu3  1  0.788  0.659  0.694  1.0
  Cu  Cu4  1  0.280  0.101  0.849  1.0
  As  As5  1  0.779  0.648  0.019  1.0
  As  As6  1  0.264  0.077  0.465  1.0
  As  As7  1  0.770  0.782  0.487  1.0
  As  As8  1  0.282  0.348  0.999  1.0
  S  S9  1  0.784  0.872  0.843  1.0
  S  S10  1  0.772  0.603  0.312  1.0
  S  S11  1  0.278  0.138  0.169  1.0
  S  S12  1  0.291  0.409  0.712  1.0
[/CIF]
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The compound described by MgCu4(AsS)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 2-coordinate geometry to two equivalent Cu(3), one As(3), two equivalent As(2), one S(1), and two equivalent S(4) atoms. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one As(2), one S(3), and two equivalent S(2) atoms to form corner-sharing CuAsS3 tetrahedra. In the second Cu site, Cu(2) is bonded to one As(1), one S(2), and two equivalent S(3) atoms to form corner-sharing CuAsS3 tetrahedra. In the third Cu site, Cu(3) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one As(3), one S(1), and two equivalent S(4) atoms. In the fourth Cu site, Cu(4) is bonded to one As(4), one S(4), and two equivalent S(1) atoms to form distorted CuAsS3 tetrahedra that share  a cornercorner with one S(3)Cu3As tetrahedra, corners with two equivalent Cu(4)AsS3 tetrahedra, and corners with four equivalent As(1)CuAs2S tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded to one Cu(2), two equivalent As(4), and one S(1) atom to form distorted AsCuAs2S tetrahedra that share  a cornercorner with one S(2)Cu3As tetrahedra, corners with two equivalent As(1)CuAs2S tetrahedra, corners with four equivalent Cu(4)AsS3 tetrahedra, and corners with four equivalent S(3)Cu3As tetrahedra. In the second As site, As(2) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(1), and two equivalent As(3) atoms. In the third As site, As(3) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(3), two equivalent As(2), and one S(2) atom. In the fourth As site, As(4) is bonded in a 4-coordinate geometry to one Cu(4), two equivalent As(1), and one S(3) atom. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(3), two equivalent Cu(4), and one As(1) atom. In the second S site, S(2) is bonded to one Cu(2), two equivalent Cu(1), and one As(3) atom to form SCu3As tetrahedra that share  a cornercorner with one As(1)CuAs2S tetrahedra, corners with two equivalent S(2)Cu3As tetrahedra, and corners with four equivalent S(3)Cu3As tetrahedra. In the third S site, S(3) is bonded to one Cu(1), two equivalent Cu(2), and one As(4) atom to form SCu3As tetrahedra that share  a cornercorner with one Cu(4)AsS3 tetrahedra, corners with two equivalent S(3)Cu3As tetrahedra, corners with four equivalent As(1)CuAs2S tetrahedra, and corners with four equivalent S(2)Cu3As tetrahedra. In the fourth S site, S(4) is bonded to two equivalent Mg(1), one Cu(4), and two equivalent Cu(3) atoms to form distorted edge-sharing SMg2Cu3 square pyramids. is represented by the CIF card [CIF]
data_MgCu4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.730
_cell_length_b   5.672
_cell_length_c   12.262
_cell_angle_alpha   84.278
_cell_angle_beta   89.122
_cell_angle_gamma   89.417
_symmetry_Int_Tables_number   1
_cell_volume   258.074
_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  0.797  0.174  0.642  1.0
  Cu  Cu1  1  0.276  0.375  0.309  1.0
  Cu  Cu2  1  0.780  0.897  0.174  1.0
  Cu  Cu3  1  0.788  0.659  0.694  1.0
  Cu  Cu4  1  0.280  0.101  0.849  1.0
  As  As5  1  0.779  0.648  0.019  1.0
  As  As6  1  0.264  0.077  0.465  1.0
  As  As7  1  0.770  0.782  0.487  1.0
  As  As8  1  0.282  0.348  0.999  1.0
  S  S9  1  0.784  0.872  0.843  1.0
  S  S10  1  0.772  0.603  0.312  1.0
  S  S11  1  0.278  0.138  0.169  1.0
  S  S12  1  0.291  0.409  0.712  1.0
[/CIF]
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