The crystal structure described by MgCu4(SO5)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra and edges with two equivalent Cu(1)O5 trigonal bipyramids. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CuO5 trigonal bipyramids that share corners with three equivalent S(1)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. In the second Cu site, Cu(2) is bonded in a linear geometry to two equivalent O(2) atoms. S(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form SO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with three equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 49-56°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one S(1) atom. In the second O site, O(2) is bonded to two equivalent Cu(1) and two equivalent Cu(2) atoms to form a mixture of corner and edge-sharing OCu4 tetrahedra. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cu(1) and one S(1) atom. is represented by the CIF file [CIF]
data_MgCu4(SO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.677
_cell_length_b   5.677
_cell_length_c   8.228
_cell_angle_alpha   96.861
_cell_angle_beta   101.536
_cell_angle_gamma   122.482
_symmetry_Int_Tables_number   1
_cell_volume   210.788
_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  0.500  0.000  0.500  1.0
  Cu  Cu1  1  0.109  0.085  0.194  1.0
  Cu  Cu2  1  0.891  0.915  0.806  1.0
  Cu  Cu3  1  0.500  0.000  0.000  1.0
  Cu  Cu4  1  0.000  0.500  0.000  1.0
  S  S5  1  0.781  0.629  0.411  1.0
  S  S6  1  0.219  0.371  0.589  1.0
  O  O7  1  0.412  0.699  0.659  1.0
  O  O8  1  0.039  0.752  0.341  1.0
  O  O9  1  0.588  0.301  0.341  1.0
  O  O10  1  0.961  0.248  0.659  1.0
  O  O11  1  0.873  0.130  0.003  1.0
  O  O12  1  0.127  0.870  0.997  1.0
  O  O13  1  0.391  0.255  0.647  1.0
  O  O14  1  0.609  0.745  0.353  1.0
  O  O15  1  0.899  0.701  0.600  1.0
  O  O16  1  0.101  0.299  0.400  1.0
[/CIF]
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The crystal structure described by MgCu4(SO5)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra and edges with two equivalent Cu(1)O5 trigonal bipyramids. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CuO5 trigonal bipyramids that share corners with three equivalent S(1)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. In the second Cu site, Cu(2) is bonded in a linear geometry to two equivalent O(2) atoms. S(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form SO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with three equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 49-56°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one S(1) atom. In the second O site, O(2) is bonded to two equivalent Cu(1) and two equivalent Cu(2) atoms to form a mixture of corner and edge-sharing OCu4 tetrahedra. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cu(1) and one S(1) atom. is represented by the CIF file [CIF]
data_MgCu4(SO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.677
_cell_length_b   5.677
_cell_length_c   8.228
_cell_angle_alpha   96.861
_cell_angle_beta   101.536
_cell_angle_gamma   122.482
_symmetry_Int_Tables_number   1
_cell_volume   210.788
_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  0.500  0.000  0.500  1.0
  Cu  Cu1  1  0.109  0.085  0.194  1.0
  Cu  Cu2  1  0.891  0.915  0.806  1.0
  Cu  Cu3  1  0.500  0.000  0.000  1.0
  Cu  Cu4  1  0.000  0.500  0.000  1.0
  S  S5  1  0.781  0.629  0.411  1.0
  S  S6  1  0.219  0.371  0.589  1.0
  O  O7  1  0.412  0.699  0.659  1.0
  O  O8  1  0.039  0.752  0.341  1.0
  O  O9  1  0.588  0.301  0.341  1.0
  O  O10  1  0.961  0.248  0.659  1.0
  O  O11  1  0.873  0.130  0.003  1.0
  O  O12  1  0.127  0.870  0.997  1.0
  O  O13  1  0.391  0.255  0.647  1.0
  O  O14  1  0.609  0.745  0.353  1.0
  O  O15  1  0.899  0.701  0.600  1.0
  O  O16  1  0.101  0.299  0.400  1.0
[/CIF]
.