The compound described by MgAl4(CuO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form distorted MgO4 tetrahedra that share corners with three equivalent Al(3)O6 octahedra, corners with three equivalent Al(4)O6 octahedra, corners with two equivalent Al(1)O4 tetrahedra, and  an edgeedge with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-66°. 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(2), one O(3), one O(6), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(6), and one O(7) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form AlO4 tetrahedra that share corners with three equivalent Al(3)O6 octahedra, corners with three equivalent Al(4)O6 octahedra, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-54°. 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 AlO4 tetrahedra that share corners with three equivalent Al(3)O6 octahedra, corners with three equivalent Al(4)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-57°. In the third Al site, Al(3) is bonded to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form AlO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Al(1)O4 tetrahedra, corners with three equivalent Al(2)O4 tetrahedra, and edges with two equivalent Al(4)O6 octahedra. In the fourth Al site, Al(4) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form AlO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Al(1)O4 tetrahedra, corners with three equivalent Al(2)O4 tetrahedra, and edges with two equivalent Al(3)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Cu(1), one Cu(2), one Al(2), and one Al(3) atom to form distorted corner-sharing OAl2Cu2 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Cu(1), one Cu(2), one Al(2), and one Al(4) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(1), one Cu(2), one Al(1), and one Al(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Al(2), one Al(3), and one Al(4) atom to form distorted OMgAl3 tetrahedra that share corners with two equivalent O(1)Al2Cu2 tetrahedra and edges with two equivalent O(5)MgAl3 tetrahedra. In the fifth O site, O(5) is bonded to one Mg(1), one Al(2), one Al(3), and one Al(4) atom to form distorted OMgAl3 tetrahedra that share corners with two equivalent O(1)Al2Cu2 tetrahedra and edges with two equivalent O(4)MgAl3 tetrahedra. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(1), one Cu(2), one Al(1), and one Al(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Cu(2), one Al(1), one Al(3), and one Al(4) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Cu(1), one Al(1), one Al(3), and one Al(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAl4(CuO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.960
_cell_length_b   6.036
_cell_length_c   5.747
_cell_angle_alpha   118.420
_cell_angle_beta   90.584
_cell_angle_gamma   60.149
_symmetry_Int_Tables_number   1
_cell_volume   150.602
_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  0.516  0.970  0.991  1.0
  Al  Al1  1  0.040  0.921  0.959  1.0
  Al  Al2  1  0.208  0.585  0.290  1.0
  Al  Al3  1  0.139  0.231  0.617  1.0
  Al  Al4  1  0.632  0.229  0.611  1.0
  Cu  Cu5  1  0.708  0.582  0.102  1.0
  Cu  Cu6  1  0.701  0.595  0.497  1.0
  O  O7  1  0.348  0.807  0.402  1.0
  O  O8  1  0.846  0.805  0.398  1.0
  O  O9  1  0.405  0.682  0.842  1.0
  O  O10  1  0.359  0.285  0.393  1.0
  O  O11  1  0.358  0.282  0.893  1.0
  O  O12  1  0.915  0.681  0.838  1.0
  O  O13  1  0.919  0.164  0.345  1.0
  O  O14  1  0.919  0.162  0.810  1.0
[/CIF]
.
The compound described by MgAl4(CuO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form distorted MgO4 tetrahedra that share corners with three equivalent Al(3)O6 octahedra, corners with three equivalent Al(4)O6 octahedra, corners with two equivalent Al(1)O4 tetrahedra, and  an edgeedge with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-66°. 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(2), one O(3), one O(6), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(6), and one O(7) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form AlO4 tetrahedra that share corners with three equivalent Al(3)O6 octahedra, corners with three equivalent Al(4)O6 octahedra, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-54°. 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 AlO4 tetrahedra that share corners with three equivalent Al(3)O6 octahedra, corners with three equivalent Al(4)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-57°. In the third Al site, Al(3) is bonded to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form AlO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Al(1)O4 tetrahedra, corners with three equivalent Al(2)O4 tetrahedra, and edges with two equivalent Al(4)O6 octahedra. In the fourth Al site, Al(4) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form AlO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Al(1)O4 tetrahedra, corners with three equivalent Al(2)O4 tetrahedra, and edges with two equivalent Al(3)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Cu(1), one Cu(2), one Al(2), and one Al(3) atom to form distorted corner-sharing OAl2Cu2 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Cu(1), one Cu(2), one Al(2), and one Al(4) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(1), one Cu(2), one Al(1), and one Al(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Al(2), one Al(3), and one Al(4) atom to form distorted OMgAl3 tetrahedra that share corners with two equivalent O(1)Al2Cu2 tetrahedra and edges with two equivalent O(5)MgAl3 tetrahedra. In the fifth O site, O(5) is bonded to one Mg(1), one Al(2), one Al(3), and one Al(4) atom to form distorted OMgAl3 tetrahedra that share corners with two equivalent O(1)Al2Cu2 tetrahedra and edges with two equivalent O(4)MgAl3 tetrahedra. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Mg(1), one Cu(1), one Cu(2), one Al(1), and one Al(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Cu(2), one Al(1), one Al(3), and one Al(4) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Cu(1), one Al(1), one Al(3), and one Al(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAl4(CuO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.960
_cell_length_b   6.036
_cell_length_c   5.747
_cell_angle_alpha   118.420
_cell_angle_beta   90.584
_cell_angle_gamma   60.149
_symmetry_Int_Tables_number   1
_cell_volume   150.602
_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  0.516  0.970  0.991  1.0
  Al  Al1  1  0.040  0.921  0.959  1.0
  Al  Al2  1  0.208  0.585  0.290  1.0
  Al  Al3  1  0.139  0.231  0.617  1.0
  Al  Al4  1  0.632  0.229  0.611  1.0
  Cu  Cu5  1  0.708  0.582  0.102  1.0
  Cu  Cu6  1  0.701  0.595  0.497  1.0
  O  O7  1  0.348  0.807  0.402  1.0
  O  O8  1  0.846  0.805  0.398  1.0
  O  O9  1  0.405  0.682  0.842  1.0
  O  O10  1  0.359  0.285  0.393  1.0
  O  O11  1  0.358  0.282  0.893  1.0
  O  O12  1  0.915  0.681  0.838  1.0
  O  O13  1  0.919  0.164  0.345  1.0
  O  O14  1  0.919  0.162  0.810  1.0
[/CIF]
.