The compound described by Al2TiO5 crystallizes in the monoclinic P2_1 space group. Ti(1) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Al(1)O6 octahedra,  a cornercorner with one Al(2)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, edges with three equivalent Al(1)O6 octahedra, and edges with three equivalent Al(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-62°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form distorted AlO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Al(2)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Al(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-62°. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form distorted AlO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Al(2)O6 octahedra, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-37°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Ti(1), one Al(1), and one Al(2) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ti(1), one Al(1), and one Al(2) atom. In the third O site, O(3) is bonded to one Ti(1), one Al(1), and two equivalent Al(2) atoms to form distorted OTiAl3 tetrahedra that share corners with two equivalent O(3)TiAl3 tetrahedra,  a cornercorner with one O(4)Ti2Al2 trigonal pyramid,  a cornercorner with one O(5)TiAl3 trigonal pyramid, edges with two equivalent O(4)Ti2Al2 trigonal pyramids, and edges with two equivalent O(5)TiAl3 trigonal pyramids. In the fourth O site, O(4) is bonded to two equivalent Ti(1), one Al(1), and one Al(2) atom to form distorted OTi2Al2 trigonal pyramids that share  a cornercorner with one O(3)TiAl3 tetrahedra,  a cornercorner with one O(5)TiAl3 trigonal pyramid, corners with two equivalent O(4)Ti2Al2 trigonal pyramids, edges with two equivalent O(3)TiAl3 tetrahedra, and edges with two equivalent O(5)TiAl3 trigonal pyramids. In the fifth O site, O(5) is bonded to one Ti(1), one Al(2), and two equivalent Al(1) atoms to form distorted OTiAl3 trigonal pyramids that share  a cornercorner with one O(3)TiAl3 tetrahedra,  a cornercorner with one O(4)Ti2Al2 trigonal pyramid, corners with two equivalent O(5)TiAl3 trigonal pyramids, edges with two equivalent O(3)TiAl3 tetrahedra, and edges with two equivalent O(4)Ti2Al2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_TiAl2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.660
_cell_length_b   5.106
_cell_length_c   9.627
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   111.064
_symmetry_Int_Tables_number   1
_cell_volume   167.875
_cell_formula_units_Z   2
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
  Ti  Ti0  1  0.129  0.255  0.062  1.0
  Ti  Ti1  1  0.871  0.745  0.562  1.0
  Al  Al2  1  0.141  0.284  0.431  1.0
  Al  Al3  1  0.188  0.379  0.755  1.0
  Al  Al4  1  0.812  0.621  0.255  1.0
  Al  Al5  1  0.859  0.716  0.931  1.0
  O  O6  1  0.056  0.117  0.612  1.0
  O  O7  1  0.044  0.088  0.881  1.0
  O  O8  1  0.247  0.492  0.254  1.0
  O  O9  1  0.315  0.633  0.579  1.0
  O  O10  1  0.308  0.616  0.925  1.0
  O  O11  1  0.685  0.367  0.079  1.0
  O  O12  1  0.692  0.384  0.425  1.0
  O  O13  1  0.753  0.508  0.754  1.0
  O  O14  1  0.944  0.883  0.112  1.0
  O  O15  1  0.956  0.912  0.381  1.0
[/CIF]
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The compound described by Al2TiO5 crystallizes in the monoclinic P2_1 space group. Ti(1) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Al(1)O6 octahedra,  a cornercorner with one Al(2)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, edges with three equivalent Al(1)O6 octahedra, and edges with three equivalent Al(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-62°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form distorted AlO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Al(2)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Al(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-62°. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form distorted AlO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Al(2)O6 octahedra, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-37°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Ti(1), one Al(1), and one Al(2) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ti(1), one Al(1), and one Al(2) atom. In the third O site, O(3) is bonded to one Ti(1), one Al(1), and two equivalent Al(2) atoms to form distorted OTiAl3 tetrahedra that share corners with two equivalent O(3)TiAl3 tetrahedra,  a cornercorner with one O(4)Ti2Al2 trigonal pyramid,  a cornercorner with one O(5)TiAl3 trigonal pyramid, edges with two equivalent O(4)Ti2Al2 trigonal pyramids, and edges with two equivalent O(5)TiAl3 trigonal pyramids. In the fourth O site, O(4) is bonded to two equivalent Ti(1), one Al(1), and one Al(2) atom to form distorted OTi2Al2 trigonal pyramids that share  a cornercorner with one O(3)TiAl3 tetrahedra,  a cornercorner with one O(5)TiAl3 trigonal pyramid, corners with two equivalent O(4)Ti2Al2 trigonal pyramids, edges with two equivalent O(3)TiAl3 tetrahedra, and edges with two equivalent O(5)TiAl3 trigonal pyramids. In the fifth O site, O(5) is bonded to one Ti(1), one Al(2), and two equivalent Al(1) atoms to form distorted OTiAl3 trigonal pyramids that share  a cornercorner with one O(3)TiAl3 tetrahedra,  a cornercorner with one O(4)Ti2Al2 trigonal pyramid, corners with two equivalent O(5)TiAl3 trigonal pyramids, edges with two equivalent O(3)TiAl3 tetrahedra, and edges with two equivalent O(4)Ti2Al2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_TiAl2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.660
_cell_length_b   5.106
_cell_length_c   9.627
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   111.064
_symmetry_Int_Tables_number   1
_cell_volume   167.875
_cell_formula_units_Z   2
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
  Ti  Ti0  1  0.129  0.255  0.062  1.0
  Ti  Ti1  1  0.871  0.745  0.562  1.0
  Al  Al2  1  0.141  0.284  0.431  1.0
  Al  Al3  1  0.188  0.379  0.755  1.0
  Al  Al4  1  0.812  0.621  0.255  1.0
  Al  Al5  1  0.859  0.716  0.931  1.0
  O  O6  1  0.056  0.117  0.612  1.0
  O  O7  1  0.044  0.088  0.881  1.0
  O  O8  1  0.247  0.492  0.254  1.0
  O  O9  1  0.315  0.633  0.579  1.0
  O  O10  1  0.308  0.616  0.925  1.0
  O  O11  1  0.685  0.367  0.079  1.0
  O  O12  1  0.692  0.384  0.425  1.0
  O  O13  1  0.753  0.508  0.754  1.0
  O  O14  1  0.944  0.883  0.112  1.0
  O  O15  1  0.956  0.912  0.381  1.0
[/CIF]
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