The material described by MgAl4(CuO4)2 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 2-coordinate geometry to one O(6) and one O(8) atom. In the second Cu site, Cu(2) is bonded in a 2-coordinate geometry to one O(3) and one O(7) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form distorted AlO6 octahedra that share corners with three equivalent Al(3)O4 tetrahedra, corners with three equivalent Al(4)O4 tetrahedra, and edges with two equivalent Al(2)O6 octahedra. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form AlO6 octahedra that share corners with two equivalent Al(3)O4 tetrahedra, corners with two equivalent Al(4)O4 tetrahedra, and edges with two equivalent Al(1)O6 octahedra. In the third Al site, Al(3) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form distorted AlO4 tetrahedra that share corners with two equivalent Al(2)O6 octahedra, corners with three equivalent Al(1)O6 octahedra, and  an edgeedge with one Al(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-59°. In the fourth Al site, Al(4) is bonded to one O(2), one O(5), one O(7), and one O(8) atom to form distorted AlO4 tetrahedra that share corners with two equivalent Al(2)O6 octahedra, corners with three equivalent Al(1)O6 octahedra, and  an edgeedge with one Al(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-58°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and one Al(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and one Al(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(2), one Al(1), and one Al(2) atom. In the fourth O site, O(4) is bonded in a distorted 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 distorted trigonal planar geometry to one Mg(1), one Al(2), and one Al(4) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(1), one Al(1), and one Al(2) atom. In the seventh O site, O(7) is bonded in a distorted 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 distorted 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   5.845
_cell_length_b   5.748
_cell_length_c   6.476
_cell_angle_alpha   120.002
_cell_angle_beta   83.313
_cell_angle_gamma   63.692
_symmetry_Int_Tables_number   1
_cell_volume   152.072
_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  0.172  0.656  0.827  1.0
  Al  Al1  1  0.846  0.308  0.156  1.0
  Al  Al2  1  0.343  0.315  0.158  1.0
  Al  Al3  1  0.188  0.077  0.485  1.0
  Al  Al4  1  0.733  0.078  0.591  1.0
  Cu  Cu5  1  0.748  0.670  0.999  1.0
  Cu  Cu6  1  0.578  0.678  0.673  1.0
  O  O7  1  0.439  0.640  0.310  1.0
  O  O8  1  0.920  0.641  0.330  1.0
  O  O9  1  0.243  0.006  0.005  1.0
  O  O10  1  0.315  0.289  0.448  1.0
  O  O11  1  0.397  0.289  0.842  1.0
  O  O12  1  0.751  0.005  0.004  1.0
  O  O13  1  0.870  0.199  0.413  1.0
  O  O14  1  0.933  0.193  0.782  1.0
[/CIF]
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The material described by MgAl4(CuO4)2 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 2-coordinate geometry to one O(6) and one O(8) atom. In the second Cu site, Cu(2) is bonded in a 2-coordinate geometry to one O(3) and one O(7) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form distorted AlO6 octahedra that share corners with three equivalent Al(3)O4 tetrahedra, corners with three equivalent Al(4)O4 tetrahedra, and edges with two equivalent Al(2)O6 octahedra. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form AlO6 octahedra that share corners with two equivalent Al(3)O4 tetrahedra, corners with two equivalent Al(4)O4 tetrahedra, and edges with two equivalent Al(1)O6 octahedra. In the third Al site, Al(3) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form distorted AlO4 tetrahedra that share corners with two equivalent Al(2)O6 octahedra, corners with three equivalent Al(1)O6 octahedra, and  an edgeedge with one Al(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-59°. In the fourth Al site, Al(4) is bonded to one O(2), one O(5), one O(7), and one O(8) atom to form distorted AlO4 tetrahedra that share corners with two equivalent Al(2)O6 octahedra, corners with three equivalent Al(1)O6 octahedra, and  an edgeedge with one Al(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-58°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and one Al(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and one Al(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(2), one Al(1), and one Al(2) atom. In the fourth O site, O(4) is bonded in a distorted 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 distorted trigonal planar geometry to one Mg(1), one Al(2), and one Al(4) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cu(1), one Al(1), and one Al(2) atom. In the seventh O site, O(7) is bonded in a distorted 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 distorted 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   5.845
_cell_length_b   5.748
_cell_length_c   6.476
_cell_angle_alpha   120.002
_cell_angle_beta   83.313
_cell_angle_gamma   63.692
_symmetry_Int_Tables_number   1
_cell_volume   152.072
_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  0.172  0.656  0.827  1.0
  Al  Al1  1  0.846  0.308  0.156  1.0
  Al  Al2  1  0.343  0.315  0.158  1.0
  Al  Al3  1  0.188  0.077  0.485  1.0
  Al  Al4  1  0.733  0.078  0.591  1.0
  Cu  Cu5  1  0.748  0.670  0.999  1.0
  Cu  Cu6  1  0.578  0.678  0.673  1.0
  O  O7  1  0.439  0.640  0.310  1.0
  O  O8  1  0.920  0.641  0.330  1.0
  O  O9  1  0.243  0.006  0.005  1.0
  O  O10  1  0.315  0.289  0.448  1.0
  O  O11  1  0.397  0.289  0.842  1.0
  O  O12  1  0.751  0.005  0.004  1.0
  O  O13  1  0.870  0.199  0.413  1.0
  O  O14  1  0.933  0.193  0.782  1.0
[/CIF]
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