The material described by Al2TiO5 crystallizes in the orthorhombic Cmcm space group. Ti(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Al(1) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing AlO6 octahedra. The corner-sharing octahedral tilt angles range from 28-50°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ti(1) and three equivalent Al(1) atoms to form distorted OTiAl3 trigonal pyramids that share  a cornercorner with one O(3)Ti2Al2 trigonal pyramid, corners with three equivalent O(1)TiAl3 trigonal pyramids, edges with two equivalent O(3)Ti2Al2 trigonal pyramids, and edges with two equivalent O(1)TiAl3 trigonal pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ti(1) and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to two equivalent Ti(1) and two equivalent Al(1) atoms to form distorted OTi2Al2 trigonal pyramids that share corners with two equivalent O(3)Ti2Al2 trigonal pyramids, corners with two equivalent O(1)TiAl3 trigonal pyramids, and edges with four equivalent O(1)TiAl3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_TiAl2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.005
_cell_length_b   5.005
_cell_length_c   9.666
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   137.938
_symmetry_Int_Tables_number   1
_cell_volume   162.226
_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  0.815  0.185  0.750  1.0
  Ti  Ti1  1  0.185  0.815  0.250  1.0
  Al  Al2  1  0.859  0.141  0.444  1.0
  Al  Al3  1  0.141  0.859  0.556  1.0
  Al  Al4  1  0.859  0.141  0.056  1.0
  Al  Al5  1  0.141  0.859  0.944  1.0
  O  O6  1  0.687  0.313  0.566  1.0
  O  O7  1  0.313  0.687  0.434  1.0
  O  O8  1  0.313  0.687  0.066  1.0
  O  O9  1  0.687  0.313  0.934  1.0
  O  O10  1  0.956  0.044  0.617  1.0
  O  O11  1  0.044  0.956  0.383  1.0
  O  O12  1  0.235  0.765  0.750  1.0
  O  O13  1  0.765  0.235  0.250  1.0
  O  O14  1  0.956  0.044  0.883  1.0
  O  O15  1  0.044  0.956  0.117  1.0
[/CIF]
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The material described by Al2TiO5 crystallizes in the orthorhombic Cmcm space group. Ti(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Al(1) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing AlO6 octahedra. The corner-sharing octahedral tilt angles range from 28-50°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ti(1) and three equivalent Al(1) atoms to form distorted OTiAl3 trigonal pyramids that share  a cornercorner with one O(3)Ti2Al2 trigonal pyramid, corners with three equivalent O(1)TiAl3 trigonal pyramids, edges with two equivalent O(3)Ti2Al2 trigonal pyramids, and edges with two equivalent O(1)TiAl3 trigonal pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ti(1) and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to two equivalent Ti(1) and two equivalent Al(1) atoms to form distorted OTi2Al2 trigonal pyramids that share corners with two equivalent O(3)Ti2Al2 trigonal pyramids, corners with two equivalent O(1)TiAl3 trigonal pyramids, and edges with four equivalent O(1)TiAl3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_TiAl2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.005
_cell_length_b   5.005
_cell_length_c   9.666
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   137.938
_symmetry_Int_Tables_number   1
_cell_volume   162.226
_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  0.815  0.185  0.750  1.0
  Ti  Ti1  1  0.185  0.815  0.250  1.0
  Al  Al2  1  0.859  0.141  0.444  1.0
  Al  Al3  1  0.141  0.859  0.556  1.0
  Al  Al4  1  0.859  0.141  0.056  1.0
  Al  Al5  1  0.141  0.859  0.944  1.0
  O  O6  1  0.687  0.313  0.566  1.0
  O  O7  1  0.313  0.687  0.434  1.0
  O  O8  1  0.313  0.687  0.066  1.0
  O  O9  1  0.687  0.313  0.934  1.0
  O  O10  1  0.956  0.044  0.617  1.0
  O  O11  1  0.044  0.956  0.383  1.0
  O  O12  1  0.235  0.765  0.750  1.0
  O  O13  1  0.765  0.235  0.250  1.0
  O  O14  1  0.956  0.044  0.883  1.0
  O  O15  1  0.044  0.956  0.117  1.0
[/CIF]
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