The structure described by Ti2Al2O7 crystallizes in the cubic Fd-3m space group. Ti(1) is bonded to six equivalent O(2) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 58°. Al(1) is bonded in a body-centered cubic geometry to two equivalent O(1) and six equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Al(1) atoms to form OAl4 tetrahedra that share corners with four equivalent O(1)Al4 tetrahedra, corners with twelve equivalent O(2)Ti2Al2 tetrahedra, and edges with six equivalent O(2)Ti2Al2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Ti(1) and two equivalent Al(1) atoms to form OTi2Al2 tetrahedra that share corners with two equivalent O(1)Al4 tetrahedra, corners with twelve equivalent O(2)Ti2Al2 tetrahedra,  an edgeedge with one O(1)Al4 tetrahedra, and edges with four equivalent O(2)Ti2Al2 tetrahedra. is represented by the CIF card [CIF]
data_Ti2Al2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.779
_cell_length_b   6.779
_cell_length_c   6.779
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   220.272
_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  0.625  0.625  0.625  1.0
  Ti  Ti1  1  0.125  0.625  0.625  1.0
  Ti  Ti2  1  0.625  0.625  0.125  1.0
  Ti  Ti3  1  0.625  0.125  0.625  1.0
  Al  Al4  1  0.125  0.125  0.125  1.0
  Al  Al5  1  0.625  0.125  0.125  1.0
  Al  Al6  1  0.125  0.125  0.625  1.0
  Al  Al7  1  0.125  0.625  0.125  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.250  0.250  0.250  1.0
  O  O10  1  0.277  0.277  0.723  1.0
  O  O11  1  0.527  0.527  0.973  1.0
  O  O12  1  0.723  0.277  0.723  1.0
  O  O13  1  0.723  0.277  0.277  1.0
  O  O14  1  0.277  0.723  0.723  1.0
  O  O15  1  0.277  0.723  0.277  1.0
  O  O16  1  0.723  0.723  0.277  1.0
  O  O17  1  0.973  0.527  0.527  1.0
  O  O18  1  0.527  0.973  0.973  1.0
  O  O19  1  0.973  0.973  0.527  1.0
  O  O20  1  0.973  0.527  0.973  1.0
  O  O21  1  0.527  0.973  0.527  1.0
[/CIF]
.
The structure described by Ti2Al2O7 crystallizes in the cubic Fd-3m space group. Ti(1) is bonded to six equivalent O(2) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 58°. Al(1) is bonded in a body-centered cubic geometry to two equivalent O(1) and six equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Al(1) atoms to form OAl4 tetrahedra that share corners with four equivalent O(1)Al4 tetrahedra, corners with twelve equivalent O(2)Ti2Al2 tetrahedra, and edges with six equivalent O(2)Ti2Al2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Ti(1) and two equivalent Al(1) atoms to form OTi2Al2 tetrahedra that share corners with two equivalent O(1)Al4 tetrahedra, corners with twelve equivalent O(2)Ti2Al2 tetrahedra,  an edgeedge with one O(1)Al4 tetrahedra, and edges with four equivalent O(2)Ti2Al2 tetrahedra. is represented by the CIF card [CIF]
data_Ti2Al2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.779
_cell_length_b   6.779
_cell_length_c   6.779
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   220.272
_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  0.625  0.625  0.625  1.0
  Ti  Ti1  1  0.125  0.625  0.625  1.0
  Ti  Ti2  1  0.625  0.625  0.125  1.0
  Ti  Ti3  1  0.625  0.125  0.625  1.0
  Al  Al4  1  0.125  0.125  0.125  1.0
  Al  Al5  1  0.625  0.125  0.125  1.0
  Al  Al6  1  0.125  0.125  0.625  1.0
  Al  Al7  1  0.125  0.625  0.125  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.250  0.250  0.250  1.0
  O  O10  1  0.277  0.277  0.723  1.0
  O  O11  1  0.527  0.527  0.973  1.0
  O  O12  1  0.723  0.277  0.723  1.0
  O  O13  1  0.723  0.277  0.277  1.0
  O  O14  1  0.277  0.723  0.723  1.0
  O  O15  1  0.277  0.723  0.277  1.0
  O  O16  1  0.723  0.723  0.277  1.0
  O  O17  1  0.973  0.527  0.527  1.0
  O  O18  1  0.527  0.973  0.973  1.0
  O  O19  1  0.973  0.973  0.527  1.0
  O  O20  1  0.973  0.527  0.973  1.0
  O  O21  1  0.527  0.973  0.527  1.0
[/CIF]
.