The material described by MgCu4(AsS)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one Cu(1), two equivalent As(2), two equivalent As(3), one S(4), and two equivalent S(2) atoms. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 5-coordinate geometry to one Mg(1), one As(2), one S(3), and two equivalent S(2) atoms. In the second Cu site, Cu(2) is bonded to one As(1), one S(2), and two equivalent S(3) atoms to form CuAsS3 tetrahedra that share  a cornercorner with one S(1)Cu3As tetrahedra and corners with two equivalent Cu(2)AsS3 tetrahedra. In the third Cu site, Cu(3) is bonded to one As(3), one S(1), and two equivalent S(4) atoms to form corner-sharing CuAsS3 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one As(4), one S(4), and two equivalent S(1) atoms to form 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 Cu(3)AsS3 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 4-coordinate geometry to one Cu(2), two equivalent As(4), and one S(1) atom. 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 two equivalent Mg(1), one Cu(3), and two equivalent As(2) atoms. 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 to one Cu(3), two equivalent Cu(4), and one As(1) atom to form SCu3As tetrahedra that share  a cornercorner with one Cu(2)AsS3 tetrahedra, corners with two equivalent S(1)Cu3As tetrahedra, and corners with four equivalent S(4)MgCu3 tetrahedra. In the second S site, S(2) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(2), and two equivalent Cu(1) atoms. 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 and corners with two equivalent S(3)Cu3As tetrahedra. In the fourth S site, S(4) is bonded to one Mg(1), one Cu(4), and two equivalent Cu(3) atoms to form SMgCu3 tetrahedra that share corners with two equivalent S(4)MgCu3 tetrahedra and corners with four equivalent S(1)Cu3As tetrahedra. is represented by the CIF card [CIF]
data_MgCu4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.697
_cell_length_b   5.593
_cell_length_c   12.419
_cell_angle_alpha   79.897
_cell_angle_beta   89.917
_cell_angle_gamma   89.993
_symmetry_Int_Tables_number   1
_cell_volume   252.801
_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  0.278  0.511  0.478  1.0
  Cu  Cu1  1  0.280  0.341  0.289  1.0
  Cu  Cu2  1  0.779  0.874  0.177  1.0
  Cu  Cu3  1  0.781  0.663  0.711  1.0
  Cu  Cu4  1  0.281  0.139  0.827  1.0
  As  As5  1  0.780  0.652  0.019  1.0
  As  As6  1  0.281  0.008  0.445  1.0
  As  As7  1  0.780  0.036  0.572  1.0
  As  As8  1  0.280  0.363  0.983  1.0
  S  S9  1  0.781  0.891  0.849  1.0
  S  S10  1  0.780  0.568  0.324  1.0
  S  S11  1  0.279  0.121  0.152  1.0
  S  S12  1  0.282  0.452  0.683  1.0
[/CIF]
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The material described by MgCu4(AsS)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one Cu(1), two equivalent As(2), two equivalent As(3), one S(4), and two equivalent S(2) atoms. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 5-coordinate geometry to one Mg(1), one As(2), one S(3), and two equivalent S(2) atoms. In the second Cu site, Cu(2) is bonded to one As(1), one S(2), and two equivalent S(3) atoms to form CuAsS3 tetrahedra that share  a cornercorner with one S(1)Cu3As tetrahedra and corners with two equivalent Cu(2)AsS3 tetrahedra. In the third Cu site, Cu(3) is bonded to one As(3), one S(1), and two equivalent S(4) atoms to form corner-sharing CuAsS3 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one As(4), one S(4), and two equivalent S(1) atoms to form 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 Cu(3)AsS3 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 4-coordinate geometry to one Cu(2), two equivalent As(4), and one S(1) atom. 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 two equivalent Mg(1), one Cu(3), and two equivalent As(2) atoms. 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 to one Cu(3), two equivalent Cu(4), and one As(1) atom to form SCu3As tetrahedra that share  a cornercorner with one Cu(2)AsS3 tetrahedra, corners with two equivalent S(1)Cu3As tetrahedra, and corners with four equivalent S(4)MgCu3 tetrahedra. In the second S site, S(2) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Cu(2), and two equivalent Cu(1) atoms. 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 and corners with two equivalent S(3)Cu3As tetrahedra. In the fourth S site, S(4) is bonded to one Mg(1), one Cu(4), and two equivalent Cu(3) atoms to form SMgCu3 tetrahedra that share corners with two equivalent S(4)MgCu3 tetrahedra and corners with four equivalent S(1)Cu3As tetrahedra. is represented by the CIF card [CIF]
data_MgCu4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.697
_cell_length_b   5.593
_cell_length_c   12.419
_cell_angle_alpha   79.897
_cell_angle_beta   89.917
_cell_angle_gamma   89.993
_symmetry_Int_Tables_number   1
_cell_volume   252.801
_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  0.278  0.511  0.478  1.0
  Cu  Cu1  1  0.280  0.341  0.289  1.0
  Cu  Cu2  1  0.779  0.874  0.177  1.0
  Cu  Cu3  1  0.781  0.663  0.711  1.0
  Cu  Cu4  1  0.281  0.139  0.827  1.0
  As  As5  1  0.780  0.652  0.019  1.0
  As  As6  1  0.281  0.008  0.445  1.0
  As  As7  1  0.780  0.036  0.572  1.0
  As  As8  1  0.280  0.363  0.983  1.0
  S  S9  1  0.781  0.891  0.849  1.0
  S  S10  1  0.780  0.568  0.324  1.0
  S  S11  1  0.279  0.121  0.152  1.0
  S  S12  1  0.282  0.452  0.683  1.0
[/CIF]
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