The crystal structure described by MgAl4(CuO4)2 is Chalcostibite-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 3-coordinate geometry to one O(1), one O(6), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one O(2), one O(3), and one O(7) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(6), one O(7), and one O(8) atom. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(1), one O(3), one O(4), one O(7), and one O(8) atom to form distorted AlO5 trigonal bipyramids that share corners with two equivalent Al(2)O4 tetrahedra and  an edgeedge with one Al(4)O5 trigonal bipyramid. In the fourth Al site, Al(4) is bonded to one O(2), one O(5), one O(6), one O(7), and one O(8) atom to form distorted AlO5 trigonal bipyramids that share corners with two equivalent Al(2)O4 tetrahedra and  an edgeedge with one Al(3)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Cu(1), one Al(2), and one Al(3) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Cu(2), one Al(2), and one Al(4) atom. In the third O site, O(3) is bonded to one Mg(1), one Cu(2), one Al(1), and one Al(3) atom to form distorted OMgAl2Cu trigonal pyramids that share  a cornercorner with one O(7)Al3Cu tetrahedra, corners with two equivalent O(8)Al3Cu tetrahedra,  an edgeedge with one O(7)Al3Cu tetrahedra, and  an edgeedge with one O(6)MgAl2Cu trigonal pyramid. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Mg(1), one Al(2), and one Al(3) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Mg(1), one Al(2), and one Al(4) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Cu(1), one Al(1), and one Al(4) atom to form distorted OMgAl2Cu trigonal pyramids that share  a cornercorner with one O(8)Al3Cu tetrahedra, corners with two equivalent O(7)Al3Cu tetrahedra,  an edgeedge with one O(8)Al3Cu tetrahedra, and  an edgeedge with one O(3)MgAl2Cu trigonal pyramid. In the seventh O site, O(7) is bonded to one Cu(2), one Al(1), one Al(3), and one Al(4) atom to form OAl3Cu tetrahedra that share  a cornercorner with one O(8)Al3Cu tetrahedra,  a cornercorner with one O(3)MgAl2Cu trigonal pyramid, corners with two equivalent O(6)MgAl2Cu trigonal pyramids,  an edgeedge with one O(8)Al3Cu tetrahedra, and  an edgeedge with one O(3)MgAl2Cu trigonal pyramid. In the eighth O site, O(8) is bonded to one Cu(1), one Al(1), one Al(3), and one Al(4) atom to form OAl3Cu tetrahedra that share  a cornercorner with one O(7)Al3Cu tetrahedra,  a cornercorner with one O(6)MgAl2Cu trigonal pyramid, corners with two equivalent O(3)MgAl2Cu trigonal pyramids,  an edgeedge with one O(7)Al3Cu tetrahedra, and  an edgeedge with one O(6)MgAl2Cu trigonal pyramid. is represented by the CIF card [CIF]
data_MgAl4(CuO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.485
_cell_length_b   5.982
_cell_length_c   5.728
_cell_angle_alpha   106.194
_cell_angle_beta   68.307
_cell_angle_gamma   68.566
_symmetry_Int_Tables_number   1
_cell_volume   168.744
_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  0.225  0.548  0.776  1.0
  Al  Al1  1  0.951  0.097  0.049  1.0
  Al  Al2  1  0.237  0.526  0.264  1.0
  Al  Al3  1  0.174  0.077  0.381  1.0
  Al  Al4  1  0.750  0.077  0.696  1.0
  Cu  Cu5  1  0.689  0.691  0.060  1.0
  Cu  Cu6  1  0.618  0.694  0.630  1.0
  O  O7  1  0.352  0.746  0.355  1.0
  O  O8  1  0.901  0.746  0.392  1.0
  O  O9  1  0.269  0.874  0.966  1.0
  O  O10  1  0.280  0.310  0.417  1.0
  O  O11  1  0.410  0.310  0.893  1.0
  O  O12  1  0.856  0.875  0.908  1.0
  O  O13  1  0.841  0.235  0.422  1.0
  O  O14  1  0.924  0.236  0.815  1.0
[/CIF]
.
The crystal structure described by MgAl4(CuO4)2 is Chalcostibite-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 3-coordinate geometry to one O(1), one O(6), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one O(2), one O(3), and one O(7) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(6), one O(7), and one O(8) atom. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(1), one O(3), one O(4), one O(7), and one O(8) atom to form distorted AlO5 trigonal bipyramids that share corners with two equivalent Al(2)O4 tetrahedra and  an edgeedge with one Al(4)O5 trigonal bipyramid. In the fourth Al site, Al(4) is bonded to one O(2), one O(5), one O(6), one O(7), and one O(8) atom to form distorted AlO5 trigonal bipyramids that share corners with two equivalent Al(2)O4 tetrahedra and  an edgeedge with one Al(3)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Cu(1), one Al(2), and one Al(3) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Cu(2), one Al(2), and one Al(4) atom. In the third O site, O(3) is bonded to one Mg(1), one Cu(2), one Al(1), and one Al(3) atom to form distorted OMgAl2Cu trigonal pyramids that share  a cornercorner with one O(7)Al3Cu tetrahedra, corners with two equivalent O(8)Al3Cu tetrahedra,  an edgeedge with one O(7)Al3Cu tetrahedra, and  an edgeedge with one O(6)MgAl2Cu trigonal pyramid. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Mg(1), one Al(2), and one Al(3) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Mg(1), one Al(2), and one Al(4) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Cu(1), one Al(1), and one Al(4) atom to form distorted OMgAl2Cu trigonal pyramids that share  a cornercorner with one O(8)Al3Cu tetrahedra, corners with two equivalent O(7)Al3Cu tetrahedra,  an edgeedge with one O(8)Al3Cu tetrahedra, and  an edgeedge with one O(3)MgAl2Cu trigonal pyramid. In the seventh O site, O(7) is bonded to one Cu(2), one Al(1), one Al(3), and one Al(4) atom to form OAl3Cu tetrahedra that share  a cornercorner with one O(8)Al3Cu tetrahedra,  a cornercorner with one O(3)MgAl2Cu trigonal pyramid, corners with two equivalent O(6)MgAl2Cu trigonal pyramids,  an edgeedge with one O(8)Al3Cu tetrahedra, and  an edgeedge with one O(3)MgAl2Cu trigonal pyramid. In the eighth O site, O(8) is bonded to one Cu(1), one Al(1), one Al(3), and one Al(4) atom to form OAl3Cu tetrahedra that share  a cornercorner with one O(7)Al3Cu tetrahedra,  a cornercorner with one O(6)MgAl2Cu trigonal pyramid, corners with two equivalent O(3)MgAl2Cu trigonal pyramids,  an edgeedge with one O(7)Al3Cu tetrahedra, and  an edgeedge with one O(6)MgAl2Cu trigonal pyramid. is represented by the CIF card [CIF]
data_MgAl4(CuO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.485
_cell_length_b   5.982
_cell_length_c   5.728
_cell_angle_alpha   106.194
_cell_angle_beta   68.307
_cell_angle_gamma   68.566
_symmetry_Int_Tables_number   1
_cell_volume   168.744
_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  0.225  0.548  0.776  1.0
  Al  Al1  1  0.951  0.097  0.049  1.0
  Al  Al2  1  0.237  0.526  0.264  1.0
  Al  Al3  1  0.174  0.077  0.381  1.0
  Al  Al4  1  0.750  0.077  0.696  1.0
  Cu  Cu5  1  0.689  0.691  0.060  1.0
  Cu  Cu6  1  0.618  0.694  0.630  1.0
  O  O7  1  0.352  0.746  0.355  1.0
  O  O8  1  0.901  0.746  0.392  1.0
  O  O9  1  0.269  0.874  0.966  1.0
  O  O10  1  0.280  0.310  0.417  1.0
  O  O11  1  0.410  0.310  0.893  1.0
  O  O12  1  0.856  0.875  0.908  1.0
  O  O13  1  0.841  0.235  0.422  1.0
  O  O14  1  0.924  0.236  0.815  1.0
[/CIF]
.