The crystal structure described by MgCr4(CuS4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 8-coordinate geometry to one Cu(1), one Cu(2), one S(1), one S(2), one S(3), one S(5), one S(7), and one S(8) atom. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(2), one S(3), one S(4), one S(5), one S(6), and one S(8) atom to form edge-sharing CrS6 octahedra. In the second Cr site, Cr(2) is bonded to one S(1), one S(3), one S(4), one S(5), one S(6), and one S(7) atom to form edge-sharing CrS6 octahedra. In the third Cr site, Cr(3) is bonded to one S(1), one S(2), one S(4), one S(6), one S(7), and one S(8) atom to form edge-sharing CrS6 octahedra. In the fourth Cr site, Cr(4) is bonded to one S(1), one S(2), one S(3), one S(5), one S(7), and one S(8) atom to form edge-sharing CrS6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 2-coordinate geometry to one Mg(1), one S(5), one S(6), and one S(7) atom. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one Mg(1), one S(2), one S(3), one S(4), and one S(7) atom. There are eight inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(2), one Cr(3), and one Cr(4) atom. In the second S site, S(2) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Cr(3), one Cr(4), and one Cu(2) atom. In the third S site, S(3) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(4), and one Cu(2) atom to form SMgCr3Cu square pyramids that share corners with four equivalent S(5)MgCr3Cu trigonal bipyramids,  a cornercorner with one S(4)Cr3Cu trigonal pyramid, corners with two equivalent S(6)Cr3Cu trigonal pyramids, edges with two equivalent S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(4)Cr3Cu trigonal pyramid. In the fourth S site, S(4) is bonded to one Cr(1), one Cr(2), one Cr(3), and one Cu(2) atom to form distorted SCr3Cu trigonal pyramids that share  a cornercorner with one S(7)MgCr3Cu2 octahedra,  a cornercorner with one S(3)MgCr3Cu square pyramid, corners with two equivalent S(5)MgCr3Cu trigonal bipyramids, corners with three equivalent S(6)Cr3Cu trigonal pyramids,  an edgeedge with one S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(3)MgCr3Cu square pyramid. The corner-sharing octahedral tilt angles are 68°. In the fifth S site, S(5) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(4), and one Cu(1) atom to form distorted SMgCr3Cu trigonal bipyramids that share corners with four equivalent S(3)MgCr3Cu square pyramids,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, corners with two equivalent S(4)Cr3Cu trigonal pyramids, edges with two equivalent S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the sixth S site, S(6) is bonded to one Cr(1), one Cr(2), one Cr(3), and one Cu(1) atom to form SCr3Cu trigonal pyramids that share  a cornercorner with one S(7)MgCr3Cu2 octahedra, corners with two equivalent S(3)MgCr3Cu square pyramids,  a cornercorner with one S(5)MgCr3Cu trigonal bipyramid, corners with three equivalent S(4)Cr3Cu trigonal pyramids,  an edgeedge with one S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(5)MgCr3Cu trigonal bipyramid. The corner-sharing octahedral tilt angles are 88°. In the seventh S site, S(7) is bonded to one Mg(1), one Cr(2), one Cr(3), one Cr(4), one Cu(1), and one Cu(2) atom to form distorted SMgCr3Cu2 octahedra that share  a cornercorner with one S(4)Cr3Cu trigonal pyramid,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, edges with two equivalent S(3)MgCr3Cu square pyramids, edges with two equivalent S(5)MgCr3Cu trigonal bipyramids,  an edgeedge with one S(4)Cr3Cu trigonal pyramid, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the eighth S site, S(8) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Cr(3), and one Cr(4) atom. is represented by the CIF card [CIF]
data_MgCr4(CuS4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.169
_cell_length_b   7.035
_cell_length_c   7.187
_cell_angle_alpha   59.351
_cell_angle_beta   60.020
_cell_angle_gamma   61.380
_symmetry_Int_Tables_number   1
_cell_volume   257.608
_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  0.556  0.930  0.014  1.0
  Cr  Cr1  1  0.498  0.473  0.513  1.0
  Cr  Cr2  1  0.498  0.472  0.026  1.0
  Cr  Cr3  1  0.502  0.961  0.523  1.0
  Cr  Cr4  1  0.002  0.470  0.519  1.0
  Cu  Cu5  1  0.010  0.981  0.703  1.0
  Cu  Cu6  1  0.101  0.110  0.145  1.0
  S  S7  1  0.746  0.716  0.750  1.0
  S  S8  1  0.257  0.221  0.746  1.0
  S  S9  1  0.261  0.696  0.274  1.0
  S  S10  1  0.717  0.236  0.276  1.0
  S  S11  1  0.713  0.266  0.762  1.0
  S  S12  1  0.291  0.684  0.765  1.0
  S  S13  1  0.254  0.218  0.286  1.0
  S  S14  1  0.744  0.713  0.300  1.0
[/CIF]
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The crystal structure described by MgCr4(CuS4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 8-coordinate geometry to one Cu(1), one Cu(2), one S(1), one S(2), one S(3), one S(5), one S(7), and one S(8) atom. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(2), one S(3), one S(4), one S(5), one S(6), and one S(8) atom to form edge-sharing CrS6 octahedra. In the second Cr site, Cr(2) is bonded to one S(1), one S(3), one S(4), one S(5), one S(6), and one S(7) atom to form edge-sharing CrS6 octahedra. In the third Cr site, Cr(3) is bonded to one S(1), one S(2), one S(4), one S(6), one S(7), and one S(8) atom to form edge-sharing CrS6 octahedra. In the fourth Cr site, Cr(4) is bonded to one S(1), one S(2), one S(3), one S(5), one S(7), and one S(8) atom to form edge-sharing CrS6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 2-coordinate geometry to one Mg(1), one S(5), one S(6), and one S(7) atom. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one Mg(1), one S(2), one S(3), one S(4), and one S(7) atom. There are eight inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cr(2), one Cr(3), and one Cr(4) atom. In the second S site, S(2) is bonded in a 5-coordinate geometry to one Mg(1), one Cr(1), one Cr(3), one Cr(4), and one Cu(2) atom. In the third S site, S(3) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(4), and one Cu(2) atom to form SMgCr3Cu square pyramids that share corners with four equivalent S(5)MgCr3Cu trigonal bipyramids,  a cornercorner with one S(4)Cr3Cu trigonal pyramid, corners with two equivalent S(6)Cr3Cu trigonal pyramids, edges with two equivalent S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(4)Cr3Cu trigonal pyramid. In the fourth S site, S(4) is bonded to one Cr(1), one Cr(2), one Cr(3), and one Cu(2) atom to form distorted SCr3Cu trigonal pyramids that share  a cornercorner with one S(7)MgCr3Cu2 octahedra,  a cornercorner with one S(3)MgCr3Cu square pyramid, corners with two equivalent S(5)MgCr3Cu trigonal bipyramids, corners with three equivalent S(6)Cr3Cu trigonal pyramids,  an edgeedge with one S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(3)MgCr3Cu square pyramid. The corner-sharing octahedral tilt angles are 68°. In the fifth S site, S(5) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(4), and one Cu(1) atom to form distorted SMgCr3Cu trigonal bipyramids that share corners with four equivalent S(3)MgCr3Cu square pyramids,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, corners with two equivalent S(4)Cr3Cu trigonal pyramids, edges with two equivalent S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the sixth S site, S(6) is bonded to one Cr(1), one Cr(2), one Cr(3), and one Cu(1) atom to form SCr3Cu trigonal pyramids that share  a cornercorner with one S(7)MgCr3Cu2 octahedra, corners with two equivalent S(3)MgCr3Cu square pyramids,  a cornercorner with one S(5)MgCr3Cu trigonal bipyramid, corners with three equivalent S(4)Cr3Cu trigonal pyramids,  an edgeedge with one S(7)MgCr3Cu2 octahedra, and  an edgeedge with one S(5)MgCr3Cu trigonal bipyramid. The corner-sharing octahedral tilt angles are 88°. In the seventh S site, S(7) is bonded to one Mg(1), one Cr(2), one Cr(3), one Cr(4), one Cu(1), and one Cu(2) atom to form distorted SMgCr3Cu2 octahedra that share  a cornercorner with one S(4)Cr3Cu trigonal pyramid,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, edges with two equivalent S(3)MgCr3Cu square pyramids, edges with two equivalent S(5)MgCr3Cu trigonal bipyramids,  an edgeedge with one S(4)Cr3Cu trigonal pyramid, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the eighth S site, S(8) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Cr(3), and one Cr(4) atom. is represented by the CIF card [CIF]
data_MgCr4(CuS4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.169
_cell_length_b   7.035
_cell_length_c   7.187
_cell_angle_alpha   59.351
_cell_angle_beta   60.020
_cell_angle_gamma   61.380
_symmetry_Int_Tables_number   1
_cell_volume   257.608
_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  0.556  0.930  0.014  1.0
  Cr  Cr1  1  0.498  0.473  0.513  1.0
  Cr  Cr2  1  0.498  0.472  0.026  1.0
  Cr  Cr3  1  0.502  0.961  0.523  1.0
  Cr  Cr4  1  0.002  0.470  0.519  1.0
  Cu  Cu5  1  0.010  0.981  0.703  1.0
  Cu  Cu6  1  0.101  0.110  0.145  1.0
  S  S7  1  0.746  0.716  0.750  1.0
  S  S8  1  0.257  0.221  0.746  1.0
  S  S9  1  0.261  0.696  0.274  1.0
  S  S10  1  0.717  0.236  0.276  1.0
  S  S11  1  0.713  0.266  0.762  1.0
  S  S12  1  0.291  0.684  0.765  1.0
  S  S13  1  0.254  0.218  0.286  1.0
  S  S14  1  0.744  0.713  0.300  1.0
[/CIF]
.