The crystal structure described by MgCr4(CuS4)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 8-coordinate geometry to one Cu(1), one Cu(2), one S(3), one S(4), two equivalent S(2), and two equivalent S(5) atoms. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(3), one S(4), two equivalent S(2), and two equivalent S(5) atoms to form edge-sharing CrS6 octahedra. In the second Cr site, Cr(2) is bonded to one S(1), one S(2), one S(3), one S(4), one S(5), and one S(6) atom to form edge-sharing CrS6 octahedra. In the third Cr site, Cr(3) is bonded to one S(1), one S(6), two equivalent S(2), and two equivalent S(5) atoms to form edge-sharing CrS6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 5-coordinate geometry to one Mg(1), one S(1), one S(4), and two equivalent S(5) atoms. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one Mg(1), one S(3), one S(6), and two equivalent S(2) atoms. There are six inequivalent S sites. In the first S site, S(1) is bonded to one Cr(3), two equivalent Cr(2), and one Cu(1) atom to form distorted SCr3Cu trigonal pyramids that share  a cornercorner with one S(4)MgCr3Cu square pyramid, corners with two equivalent S(3)MgCr3Cu square pyramids, corners with two equivalent S(5)MgCr3Cu square pyramids, corners with four equivalent S(2)MgCr3Cu square pyramids, corners with three equivalent S(6)Cr3Cu trigonal pyramids,  an edgeedge with one S(4)MgCr3Cu square pyramid, and edges with two equivalent S(5)MgCr3Cu square pyramids. In the second S site, S(2) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(3), and one Cu(2) atom to form SMgCr3Cu square pyramids that share  a cornercorner with one S(4)MgCr3Cu square pyramid, corners with five equivalent S(5)MgCr3Cu square pyramids,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, corners with two equivalent S(1)Cr3Cu trigonal pyramids,  an edgeedge with one S(4)MgCr3Cu square pyramid,  an edgeedge with one S(5)MgCr3Cu square pyramid, edges with two equivalent S(2)MgCr3Cu square pyramids, edges with two equivalent S(3)MgCr3Cu square pyramids, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the third S site, S(3) is bonded to one Mg(1), one Cr(1), two equivalent Cr(2), and one Cu(2) atom to form SMgCr3Cu square pyramids that share corners with two equivalent S(5)MgCr3Cu square pyramids, corners with four equivalent S(4)MgCr3Cu square pyramids,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, corners with two equivalent S(1)Cr3Cu trigonal pyramids, edges with two equivalent S(5)MgCr3Cu square pyramids, edges with four equivalent S(2)MgCr3Cu square pyramids, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the fourth S site, S(4) is bonded to one Mg(1), one Cr(1), two equivalent Cr(2), and one Cu(1) atom to form SMgCr3Cu square pyramids that share corners with two equivalent S(2)MgCr3Cu square pyramids, corners with four equivalent S(3)MgCr3Cu square pyramids,  a cornercorner with one S(1)Cr3Cu trigonal pyramid, corners with two equivalent S(6)Cr3Cu trigonal pyramids, edges with two equivalent S(2)MgCr3Cu square pyramids, edges with four equivalent S(5)MgCr3Cu square pyramids, and  an edgeedge with one S(1)Cr3Cu trigonal pyramid. In the fifth S site, S(5) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(3), and one Cu(1) atom to form SMgCr3Cu square pyramids that share  a cornercorner with one S(3)MgCr3Cu square pyramid, corners with five equivalent S(2)MgCr3Cu square pyramids,  a cornercorner with one S(1)Cr3Cu trigonal pyramid, corners with two equivalent S(6)Cr3Cu trigonal pyramids,  an edgeedge with one S(2)MgCr3Cu square pyramid,  an edgeedge with one S(3)MgCr3Cu square pyramid, edges with two equivalent S(4)MgCr3Cu square pyramids, edges with two equivalent S(5)MgCr3Cu square pyramids, and  an edgeedge with one S(1)Cr3Cu trigonal pyramid. In the sixth S site, S(6) is bonded to one Cr(3), two equivalent Cr(2), and one Cu(2) atom to form distorted SCr3Cu trigonal pyramids that share  a cornercorner with one S(3)MgCr3Cu square pyramid, corners with two equivalent S(2)MgCr3Cu square pyramids, corners with two equivalent S(4)MgCr3Cu square pyramids, corners with four equivalent S(5)MgCr3Cu square pyramids, corners with three equivalent S(1)Cr3Cu trigonal pyramids,  an edgeedge with one S(3)MgCr3Cu square pyramid, and edges with two equivalent S(2)MgCr3Cu square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCr4(CuS4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.211
_cell_length_b   7.213
_cell_length_c   7.214
_cell_angle_alpha   58.122
_cell_angle_beta   58.133
_cell_angle_gamma   58.149
_symmetry_Int_Tables_number   1
_cell_volume   253.985
_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  1.000  0.000  1.000  1.0
  Cr  Cr1  1  0.500  0.500  0.500  1.0
  Cr  Cr2  1  0.500  0.500  1.000  1.0
  Cr  Cr3  1  0.500  0.000  0.500  1.0
  Cr  Cr4  1  1.000  0.500  0.500  1.0
  Cu  Cu5  1  0.859  0.859  0.859  1.0
  Cu  Cu6  1  0.141  0.140  0.142  1.0
  S  S7  1  0.736  0.736  0.736  1.0
  S  S8  1  0.258  0.258  0.728  1.0
  S  S9  1  0.258  0.727  0.258  1.0
  S  S10  1  0.728  0.258  0.258  1.0
  S  S11  1  0.742  0.273  0.742  1.0
  S  S12  1  0.272  0.742  0.742  1.0
  S  S13  1  0.264  0.264  0.264  1.0
  S  S14  1  0.742  0.742  0.272  1.0
[/CIF]
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The crystal structure described by MgCr4(CuS4)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 8-coordinate geometry to one Cu(1), one Cu(2), one S(3), one S(4), two equivalent S(2), and two equivalent S(5) atoms. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(3), one S(4), two equivalent S(2), and two equivalent S(5) atoms to form edge-sharing CrS6 octahedra. In the second Cr site, Cr(2) is bonded to one S(1), one S(2), one S(3), one S(4), one S(5), and one S(6) atom to form edge-sharing CrS6 octahedra. In the third Cr site, Cr(3) is bonded to one S(1), one S(6), two equivalent S(2), and two equivalent S(5) atoms to form edge-sharing CrS6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 5-coordinate geometry to one Mg(1), one S(1), one S(4), and two equivalent S(5) atoms. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one Mg(1), one S(3), one S(6), and two equivalent S(2) atoms. There are six inequivalent S sites. In the first S site, S(1) is bonded to one Cr(3), two equivalent Cr(2), and one Cu(1) atom to form distorted SCr3Cu trigonal pyramids that share  a cornercorner with one S(4)MgCr3Cu square pyramid, corners with two equivalent S(3)MgCr3Cu square pyramids, corners with two equivalent S(5)MgCr3Cu square pyramids, corners with four equivalent S(2)MgCr3Cu square pyramids, corners with three equivalent S(6)Cr3Cu trigonal pyramids,  an edgeedge with one S(4)MgCr3Cu square pyramid, and edges with two equivalent S(5)MgCr3Cu square pyramids. In the second S site, S(2) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(3), and one Cu(2) atom to form SMgCr3Cu square pyramids that share  a cornercorner with one S(4)MgCr3Cu square pyramid, corners with five equivalent S(5)MgCr3Cu square pyramids,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, corners with two equivalent S(1)Cr3Cu trigonal pyramids,  an edgeedge with one S(4)MgCr3Cu square pyramid,  an edgeedge with one S(5)MgCr3Cu square pyramid, edges with two equivalent S(2)MgCr3Cu square pyramids, edges with two equivalent S(3)MgCr3Cu square pyramids, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the third S site, S(3) is bonded to one Mg(1), one Cr(1), two equivalent Cr(2), and one Cu(2) atom to form SMgCr3Cu square pyramids that share corners with two equivalent S(5)MgCr3Cu square pyramids, corners with four equivalent S(4)MgCr3Cu square pyramids,  a cornercorner with one S(6)Cr3Cu trigonal pyramid, corners with two equivalent S(1)Cr3Cu trigonal pyramids, edges with two equivalent S(5)MgCr3Cu square pyramids, edges with four equivalent S(2)MgCr3Cu square pyramids, and  an edgeedge with one S(6)Cr3Cu trigonal pyramid. In the fourth S site, S(4) is bonded to one Mg(1), one Cr(1), two equivalent Cr(2), and one Cu(1) atom to form SMgCr3Cu square pyramids that share corners with two equivalent S(2)MgCr3Cu square pyramids, corners with four equivalent S(3)MgCr3Cu square pyramids,  a cornercorner with one S(1)Cr3Cu trigonal pyramid, corners with two equivalent S(6)Cr3Cu trigonal pyramids, edges with two equivalent S(2)MgCr3Cu square pyramids, edges with four equivalent S(5)MgCr3Cu square pyramids, and  an edgeedge with one S(1)Cr3Cu trigonal pyramid. In the fifth S site, S(5) is bonded to one Mg(1), one Cr(1), one Cr(2), one Cr(3), and one Cu(1) atom to form SMgCr3Cu square pyramids that share  a cornercorner with one S(3)MgCr3Cu square pyramid, corners with five equivalent S(2)MgCr3Cu square pyramids,  a cornercorner with one S(1)Cr3Cu trigonal pyramid, corners with two equivalent S(6)Cr3Cu trigonal pyramids,  an edgeedge with one S(2)MgCr3Cu square pyramid,  an edgeedge with one S(3)MgCr3Cu square pyramid, edges with two equivalent S(4)MgCr3Cu square pyramids, edges with two equivalent S(5)MgCr3Cu square pyramids, and  an edgeedge with one S(1)Cr3Cu trigonal pyramid. In the sixth S site, S(6) is bonded to one Cr(3), two equivalent Cr(2), and one Cu(2) atom to form distorted SCr3Cu trigonal pyramids that share  a cornercorner with one S(3)MgCr3Cu square pyramid, corners with two equivalent S(2)MgCr3Cu square pyramids, corners with two equivalent S(4)MgCr3Cu square pyramids, corners with four equivalent S(5)MgCr3Cu square pyramids, corners with three equivalent S(1)Cr3Cu trigonal pyramids,  an edgeedge with one S(3)MgCr3Cu square pyramid, and edges with two equivalent S(2)MgCr3Cu square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCr4(CuS4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.211
_cell_length_b   7.213
_cell_length_c   7.214
_cell_angle_alpha   58.122
_cell_angle_beta   58.133
_cell_angle_gamma   58.149
_symmetry_Int_Tables_number   1
_cell_volume   253.985
_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  1.000  0.000  1.000  1.0
  Cr  Cr1  1  0.500  0.500  0.500  1.0
  Cr  Cr2  1  0.500  0.500  1.000  1.0
  Cr  Cr3  1  0.500  0.000  0.500  1.0
  Cr  Cr4  1  1.000  0.500  0.500  1.0
  Cu  Cu5  1  0.859  0.859  0.859  1.0
  Cu  Cu6  1  0.141  0.140  0.142  1.0
  S  S7  1  0.736  0.736  0.736  1.0
  S  S8  1  0.258  0.258  0.728  1.0
  S  S9  1  0.258  0.727  0.258  1.0
  S  S10  1  0.728  0.258  0.258  1.0
  S  S11  1  0.742  0.273  0.742  1.0
  S  S12  1  0.272  0.742  0.742  1.0
  S  S13  1  0.264  0.264  0.264  1.0
  S  S14  1  0.742  0.742  0.272  1.0
[/CIF]
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