The crystal structure described by MgAl4(HO)12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one H(10), one O(1), one O(10), one O(11), 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(12), one O(4), one O(7), one O(8), and one O(9) atom to form AlO6 octahedra that share  a cornercorner with one Al(2)O5 trigonal bipyramid and edges with two equivalent Al(3)O6 octahedra. In the second Al site, Al(2) is bonded to one O(10), one O(11), one O(2), one O(3), and one O(8) atom to form distorted AlO5 trigonal bipyramids that share  a cornercorner with one Al(1)O6 octahedra,  a cornercorner with one Al(4)O5 trigonal bipyramid, and  an edgeedge with one Al(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 56°. In the third Al site, Al(3) is bonded to one O(1), one O(12), one O(4), one O(5), one O(6), and one O(9) atom to form AlO6 octahedra that share edges with two equivalent Al(1)O6 octahedra and  an edgeedge with one Al(4)O5 trigonal bipyramid. In the fourth Al site, Al(4) is bonded to one O(10), one O(2), one O(3), one O(5), and one O(6) atom to form distorted AlO5 trigonal bipyramids that share  a cornercorner with one Al(2)O5 trigonal bipyramid,  an edgeedge with one Al(3)O6 octahedra, and  an edgeedge with one Al(2)O5 trigonal bipyramid. There are twelve inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(3) atom. In the fourth H site, H(4) is bonded in a 1-coordinate geometry to one H(10) and one O(4) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(5) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(6) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(7) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(8) atom. In the ninth H site, H(9) is bonded in a single-bond geometry to one O(9) atom. In the tenth H site, H(10) is bonded in an L-shaped geometry to one Mg(1) and one H(4) atom. In the eleventh H site, H(11) is bonded in a distorted single-bond geometry to one O(11) and one O(4) atom. In the twelfth H site, H(12) is bonded in a single-bond geometry to one O(12) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Mg(1), one Al(1), one Al(3), and one H(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Al(2), one Al(4), and one H(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Al(2), one Al(4), and one H(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Al(1), one Al(3), one H(11), and one H(4) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Al(3), one Al(4), and one H(5) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to one Al(3), one Al(4), and one H(6) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Mg(1), one Al(1), and one H(7) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Al(1), one Al(2), and one H(8) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Al(1), one Al(3), and one H(9) atom. In the tenth O site, O(10) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Al(2), and one Al(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mg(1), one Al(2), and one H(11) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Al(1), one Al(3), and one H(12) atom. is represented by the CIF file [CIF]
data_MgAl4(HO)12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.593
_cell_length_b   7.822
_cell_length_c   7.879
_cell_angle_alpha   107.557
_cell_angle_beta   138.799
_cell_angle_gamma   91.110
_symmetry_Int_Tables_number   1
_cell_volume   234.726
_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  0.320  0.166  0.026  1.0
  Al  Al1  1  0.443  0.822  0.271  1.0
  Al  Al2  1  0.594  0.168  0.780  1.0
  Al  Al3  1  0.930  0.658  0.612  1.0
  Al  Al4  1  0.039  0.328  0.411  1.0
  H  H5  1  0.024  0.943  0.548  1.0
  H  H6  1  0.987  0.970  0.264  1.0
  H  H7  1  0.616  0.516  0.928  1.0
  H  H8  1  0.365  0.430  0.020  1.0
  H  H9  1  0.191  0.664  0.472  1.0
  H  H10  1  0.804  0.307  0.555  1.0
  H  H11  1  0.289  0.101  0.277  1.0
  H  H12  1  0.659  0.854  0.703  1.0
  H  H13  1  0.513  0.881  0.009  1.0
  H  H14  1  0.318  0.347  0.898  1.0
  H  H15  1  0.178  0.416  0.134  1.0
  H  H16  1  0.810  0.609  0.836  1.0
  O  O17  1  0.954  0.919  0.616  1.0
  O  O18  1  0.128  0.096  0.438  1.0
  O  O19  1  0.515  0.414  0.749  1.0
  O  O20  1  0.484  0.603  0.304  1.0
  O  O21  1  0.026  0.571  0.416  1.0
  O  O22  1  0.867  0.390  0.517  1.0
  O  O23  1  0.455  0.074  0.307  1.0
  O  O24  1  0.505  0.911  0.580  1.0
  O  O25  1  0.410  0.770  0.988  1.0
  O  O26  1  0.636  0.164  0.029  1.0
  O  O27  1  0.034  0.273  0.025  1.0
  O  O28  1  0.961  0.720  0.899  1.0
[/CIF]
.
The crystal structure described by MgAl4(HO)12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one H(10), one O(1), one O(10), one O(11), 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(12), one O(4), one O(7), one O(8), and one O(9) atom to form AlO6 octahedra that share  a cornercorner with one Al(2)O5 trigonal bipyramid and edges with two equivalent Al(3)O6 octahedra. In the second Al site, Al(2) is bonded to one O(10), one O(11), one O(2), one O(3), and one O(8) atom to form distorted AlO5 trigonal bipyramids that share  a cornercorner with one Al(1)O6 octahedra,  a cornercorner with one Al(4)O5 trigonal bipyramid, and  an edgeedge with one Al(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 56°. In the third Al site, Al(3) is bonded to one O(1), one O(12), one O(4), one O(5), one O(6), and one O(9) atom to form AlO6 octahedra that share edges with two equivalent Al(1)O6 octahedra and  an edgeedge with one Al(4)O5 trigonal bipyramid. In the fourth Al site, Al(4) is bonded to one O(10), one O(2), one O(3), one O(5), and one O(6) atom to form distorted AlO5 trigonal bipyramids that share  a cornercorner with one Al(2)O5 trigonal bipyramid,  an edgeedge with one Al(3)O6 octahedra, and  an edgeedge with one Al(2)O5 trigonal bipyramid. There are twelve inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(3) atom. In the fourth H site, H(4) is bonded in a 1-coordinate geometry to one H(10) and one O(4) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(5) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(6) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(7) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(8) atom. In the ninth H site, H(9) is bonded in a single-bond geometry to one O(9) atom. In the tenth H site, H(10) is bonded in an L-shaped geometry to one Mg(1) and one H(4) atom. In the eleventh H site, H(11) is bonded in a distorted single-bond geometry to one O(11) and one O(4) atom. In the twelfth H site, H(12) is bonded in a single-bond geometry to one O(12) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Mg(1), one Al(1), one Al(3), and one H(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Al(2), one Al(4), and one H(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Al(2), one Al(4), and one H(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Al(1), one Al(3), one H(11), and one H(4) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Al(3), one Al(4), and one H(5) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to one Al(3), one Al(4), and one H(6) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Mg(1), one Al(1), and one H(7) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Al(1), one Al(2), and one H(8) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Al(1), one Al(3), and one H(9) atom. In the tenth O site, O(10) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Al(2), and one Al(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mg(1), one Al(2), and one H(11) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Al(1), one Al(3), and one H(12) atom. is represented by the CIF file [CIF]
data_MgAl4(HO)12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.593
_cell_length_b   7.822
_cell_length_c   7.879
_cell_angle_alpha   107.557
_cell_angle_beta   138.799
_cell_angle_gamma   91.110
_symmetry_Int_Tables_number   1
_cell_volume   234.726
_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  0.320  0.166  0.026  1.0
  Al  Al1  1  0.443  0.822  0.271  1.0
  Al  Al2  1  0.594  0.168  0.780  1.0
  Al  Al3  1  0.930  0.658  0.612  1.0
  Al  Al4  1  0.039  0.328  0.411  1.0
  H  H5  1  0.024  0.943  0.548  1.0
  H  H6  1  0.987  0.970  0.264  1.0
  H  H7  1  0.616  0.516  0.928  1.0
  H  H8  1  0.365  0.430  0.020  1.0
  H  H9  1  0.191  0.664  0.472  1.0
  H  H10  1  0.804  0.307  0.555  1.0
  H  H11  1  0.289  0.101  0.277  1.0
  H  H12  1  0.659  0.854  0.703  1.0
  H  H13  1  0.513  0.881  0.009  1.0
  H  H14  1  0.318  0.347  0.898  1.0
  H  H15  1  0.178  0.416  0.134  1.0
  H  H16  1  0.810  0.609  0.836  1.0
  O  O17  1  0.954  0.919  0.616  1.0
  O  O18  1  0.128  0.096  0.438  1.0
  O  O19  1  0.515  0.414  0.749  1.0
  O  O20  1  0.484  0.603  0.304  1.0
  O  O21  1  0.026  0.571  0.416  1.0
  O  O22  1  0.867  0.390  0.517  1.0
  O  O23  1  0.455  0.074  0.307  1.0
  O  O24  1  0.505  0.911  0.580  1.0
  O  O25  1  0.410  0.770  0.988  1.0
  O  O26  1  0.636  0.164  0.029  1.0
  O  O27  1  0.034  0.273  0.025  1.0
  O  O28  1  0.961  0.720  0.899  1.0
[/CIF]
.