data_TiAl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.46
_cell_length_b   12.46
_cell_length_c   12.46
_cell_angle_alpha   161.67
_cell_angle_beta   161.67
_cell_angle_gamma   26.03
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TiAl2
_chemical_formula_sum   'Ti4 Al8'
_cell_volume   191.26
_cell_formula_units_Z   4
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  0.0  0.98  0.18  1.0
  Ti  Ti1  1  0.0  0.0  0.39  1.0
  Ti  Ti2  1  0.0  0.98  0.96  1.0
  Ti  Ti3  1  0.0  0.0  0.89  1.0
  Al  Al4  1  0.0  0.0  0.04  1.0
  Al  Al5  1  0.0  0.0  0.08  1.0
  Al  Al6  1  0.0  0.0  0.21  1.0
  Al  Al7  1  0.98  0.0  0.17  1.0
  Al  Al8  1  0.98  0.0  0.97  1.0
  Al  Al9  1  0.98  0.0  0.14  1.0
  Al  Al10  1  0.98  0.0  0.01  1.0
  Al  Al11  1  0.0  0.0  0.25  1.0

data_TiAl2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.97
_cell_length_b   3.97
_cell_length_c   12.46
_cell_angle_alpha   99.16
_cell_angle_beta   99.16
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TiAl2
_chemical_formula_sum   'Ti4 Al8'
_cell_volume   191.26
_cell_formula_units_Z   4
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  0.02  0.98  0.02  1.0
  Ti  Ti1  1  0.11  0.0  0.11  1.0
  Ti  Ti2  1  0.61  0.0  0.61  1.0
  Ti  Ti3  1  0.8  0.98  0.8  1.0
  Al  Al4  1  0.03  0.0  0.02  1.0
  Al  Al5  1  0.75  0.0  0.75  1.0
  Al  Al6  1  0.79  0.0  0.79  1.0
  Al  Al7  1  0.83  0.0  0.81  1.0
  Al  Al8  1  0.86  0.0  0.85  1.0
  Al  Al9  1  0.92  0.0  0.92  1.0
  Al  Al10  1  0.96  0.0  0.96  1.0
  Al  Al11  1  0.99  0.0  0.98  1.0

Ti Ti Ti Ti Al Al Al Al Al Al Al Al
TiAl2 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one TiAl2 cluster. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a bent 120 degrees geometry to one Al(3) and one Al(4) atom. The Ti(1)-Al(3) bond length is 0.15 Å. The Ti(1)-Al(4) bond length is 0.13 Å. In the second Ti site, Ti(2) is bonded in a single-bond geometry to one Al(8) atom. The Ti(2)-Al(8) bond length is 1.86 Å. In the third Ti site, Ti(3) is bonded in a single-bond geometry to one Ti(4) and one Al(5) atom. The Ti(3)-Ti(4) bond length is 1.07 Å. The Ti(3)-Al(5) bond length is 0.13 Å. In the fourth Ti site, Ti(4) is bonded in a single-bond geometry to one Ti(3) atom. There are eight inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted linear geometry to one Al(2) and one Al(7) atom. The Al(1)-Al(2) bond length is 0.47 Å. The Al(1)-Al(7) bond length is 0.24 Å. In the second Al site, Al(2) is bonded in a linear geometry to one Al(1) and one Al(6) atom. The Al(2)-Al(6) bond length is 0.93 Å. In the third Al site, Al(3) is bonded in a distorted single-bond geometry to one Ti(1) and one Al(8) atom. The Al(3)-Al(8) bond length is 0.47 Å. In the fourth Al site, Al(4) is bonded in a single-bond geometry to one Ti(1) and one Al(6) atom. The Al(4)-Al(6) bond length is 0.47 Å. In the fifth Al site, Al(5) is bonded in a single-bond geometry to one Ti(3) and one Al(7) atom. The Al(5)-Al(7) bond length is 0.47 Å. In the sixth Al site, Al(6) is bonded in a linear geometry to one Al(2) and one Al(4) atom. In the seventh Al site, Al(7) is bonded in a distorted linear geometry to one Al(1) and one Al(5) atom. In the eighth Al site, Al(8) is bonded in a distorted linear geometry to one Ti(2) and one Al(3) atom.