The crystal structure described by MgTl4Al4O12 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a rectangular see-saw-like geometry to one Tl(2), one O(5), one O(8), and two equivalent O(3) atoms. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted rectangular see-saw-like geometry to one O(5), one O(8), and two equivalent O(2) atoms. In the second Tl site, Tl(2) is bonded in a 5-coordinate geometry to one Mg(1), one O(5), one O(8), and two equivalent O(2) atoms. In the third Tl site, Tl(3) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(4), and two equivalent O(7) atoms. In the fourth Tl site, Tl(4) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(6), and two equivalent O(7) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(3), one O(6), one O(7), and one O(8) atom to form distorted corner-sharing AlO5 trigonal bipyramids. In the second Al site, Al(2) is bonded to one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form corner-sharing AlO5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Tl(3), one Tl(4), and two equivalent Al(1) atoms to form distorted OAl2Tl2 tetrahedra that share corners with two equivalent O(8)MgAl2Tl2 trigonal bipyramids and  an edgeedge with one O(4)Al2Tl2 trigonal pyramid. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Tl(1), one Tl(2), and one Al(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Al(1), and one Al(2) atom. In the fourth O site, O(4) is bonded to one Tl(3), one Tl(4), and two equivalent Al(2) atoms to form distorted edge-sharing OAl2Tl2 trigonal pyramids. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Mg(1), one Tl(1), one Tl(2), and two equivalent Al(2) atoms. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Tl(4), one Al(1), and one Al(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Tl(3), one Tl(4), and one Al(1) atom. In the eighth O site, O(8) is bonded to one Mg(1), one Tl(1), one Tl(2), and two equivalent Al(1) atoms to form corner-sharing OMgAl2Tl2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAl4Tl4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.893
_cell_length_b   6.148
_cell_length_c   7.869
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   111.964
_symmetry_Int_Tables_number   1
_cell_volume   264.409
_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  0.295  0.728  0.750  1.0
  Al  Al1  1  0.990  0.506  0.040  1.0
  Al  Al2  1  0.990  0.506  0.460  1.0
  Al  Al3  1  0.429  0.049  0.019  1.0
  Al  Al4  1  0.429  0.049  0.481  1.0
  Tl  Tl5  1  0.930  0.099  0.750  1.0
  Tl  Tl6  1  0.577  0.476  0.750  1.0
  Tl  Tl7  1  0.491  0.514  0.250  1.0
  Tl  Tl8  1  0.951  0.025  0.250  1.0
  O  O9  1  0.104  0.440  0.250  1.0
  O  O10  1  0.217  0.182  0.549  1.0
  O  O11  1  0.217  0.182  0.951  1.0
  O  O12  1  0.288  0.737  0.001  1.0
  O  O13  1  0.288  0.737  0.499  1.0
  O  O14  1  0.364  0.096  0.250  1.0
  O  O15  1  0.540  0.046  0.750  1.0
  O  O16  1  0.756  0.204  0.045  1.0
  O  O17  1  0.756  0.204  0.455  1.0
  O  O18  1  0.799  0.680  0.073  1.0
  O  O19  1  0.799  0.680  0.427  1.0
  O  O20  1  0.975  0.483  0.750  1.0
[/CIF]
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The crystal structure described by MgTl4Al4O12 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a rectangular see-saw-like geometry to one Tl(2), one O(5), one O(8), and two equivalent O(3) atoms. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted rectangular see-saw-like geometry to one O(5), one O(8), and two equivalent O(2) atoms. In the second Tl site, Tl(2) is bonded in a 5-coordinate geometry to one Mg(1), one O(5), one O(8), and two equivalent O(2) atoms. In the third Tl site, Tl(3) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(4), and two equivalent O(7) atoms. In the fourth Tl site, Tl(4) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(6), and two equivalent O(7) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(3), one O(6), one O(7), and one O(8) atom to form distorted corner-sharing AlO5 trigonal bipyramids. In the second Al site, Al(2) is bonded to one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form corner-sharing AlO5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Tl(3), one Tl(4), and two equivalent Al(1) atoms to form distorted OAl2Tl2 tetrahedra that share corners with two equivalent O(8)MgAl2Tl2 trigonal bipyramids and  an edgeedge with one O(4)Al2Tl2 trigonal pyramid. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Tl(1), one Tl(2), and one Al(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Al(1), and one Al(2) atom. In the fourth O site, O(4) is bonded to one Tl(3), one Tl(4), and two equivalent Al(2) atoms to form distorted edge-sharing OAl2Tl2 trigonal pyramids. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Mg(1), one Tl(1), one Tl(2), and two equivalent Al(2) atoms. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Tl(4), one Al(1), and one Al(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Tl(3), one Tl(4), and one Al(1) atom. In the eighth O site, O(8) is bonded to one Mg(1), one Tl(1), one Tl(2), and two equivalent Al(1) atoms to form corner-sharing OMgAl2Tl2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAl4Tl4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.893
_cell_length_b   6.148
_cell_length_c   7.869
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   111.964
_symmetry_Int_Tables_number   1
_cell_volume   264.409
_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  0.295  0.728  0.750  1.0
  Al  Al1  1  0.990  0.506  0.040  1.0
  Al  Al2  1  0.990  0.506  0.460  1.0
  Al  Al3  1  0.429  0.049  0.019  1.0
  Al  Al4  1  0.429  0.049  0.481  1.0
  Tl  Tl5  1  0.930  0.099  0.750  1.0
  Tl  Tl6  1  0.577  0.476  0.750  1.0
  Tl  Tl7  1  0.491  0.514  0.250  1.0
  Tl  Tl8  1  0.951  0.025  0.250  1.0
  O  O9  1  0.104  0.440  0.250  1.0
  O  O10  1  0.217  0.182  0.549  1.0
  O  O11  1  0.217  0.182  0.951  1.0
  O  O12  1  0.288  0.737  0.001  1.0
  O  O13  1  0.288  0.737  0.499  1.0
  O  O14  1  0.364  0.096  0.250  1.0
  O  O15  1  0.540  0.046  0.750  1.0
  O  O16  1  0.756  0.204  0.045  1.0
  O  O17  1  0.756  0.204  0.455  1.0
  O  O18  1  0.799  0.680  0.073  1.0
  O  O19  1  0.799  0.680  0.427  1.0
  O  O20  1  0.975  0.483  0.750  1.0
[/CIF]
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