data_TiAl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.44
_cell_length_b   4.44
_cell_length_c   8.09
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TiAl
_chemical_formula_sum   'Ti4 Al4'
_cell_volume   138.02
_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  Ti4  1  0.0  0.0  0.02  1.0
  Ti  Ti5  1  0.0  0.0  0.07  1.0
  Ti  Ti6  1  0.22  0.28  0.07  1.0
  Ti  Ti7  1  0.0  0.56  0.02  1.0
  Al  Al0  1  0.22  0.28  0.7  1.0
  Al  Al1  1  0.0  0.56  0.75  1.0
  Al  Al2  1  0.0  0.56  0.39  1.0
  Al  Al3  1  0.22  0.28  0.35  1.0

data_TiAl
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.44
_cell_length_b   4.44
_cell_length_c   8.09
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TiAl
_chemical_formula_sum   'Ti4 Al4'
_cell_volume   138.02
_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  0.0  0.02  1.0
  Ti  Ti1  1  0.0  0.0  0.07  1.0
  Ti  Ti2  1  0.0  0.56  0.02  1.0
  Ti  Ti3  1  0.22  0.28  0.07  1.0
  Al  Al4  1  0.0  0.56  0.39  1.0
  Al  Al5  1  0.0  0.56  0.75  1.0
  Al  Al6  1  0.22  0.28  0.35  1.0
  Al  Al7  1  0.22  0.28  0.7  1.0

Ti Ti Ti Ti Al Al Al Al
Ti Ti Ti Ti Al Al Al Al 0 1 o o o 0 2 o o o 0 3 o - o 1 2 o o o 1 3 o - o 2 3 o o o 2 7 o o o 3 5 o o - 4 5 o o o 6 7 o o o 
TiAl crystallizes in the triclinic P1 space group. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a single-bond geometry to one Ti(2) and one Ti(3) atom. The Ti(1)-Ti(2) bond length is 0.38 Å. The Ti(1)-Ti(3) bond length is 1.20 Å. In the second Ti site, Ti(2) is bonded in a single-bond geometry to one Ti(1), one Ti(3), and one Al(4) atom. The Ti(2)-Ti(3) bond length is 1.13 Å. The Ti(2)-Al(4) bond length is 2.51 Å. In the third Ti site, Ti(3) is bonded in a 4-coordinate geometry to one Ti(1), one Ti(2), one Ti(4), and one Al(4) atom. The Ti(3)-Ti(4) bond length is 1.96 Å. The Ti(3)-Al(4) bond length is 2.24 Å. In the fourth Ti site, Ti(4) is bonded in a 2-coordinate geometry to one Ti(3) and one Al(2) atom. The Ti(4)-Al(2) bond length is 2.24 Å. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 1-coordinate geometry to one Al(2) and one Al(4) atom. The Al(1)-Al(2) bond length is 1.96 Å. The Al(1)-Al(4) bond length is 2.85 Å. In the second Al site, Al(2) is bonded in a 2-coordinate geometry to one Ti(4) and one Al(1) atom. In the third Al site, Al(3) is bonded in a 1-coordinate geometry to three equivalent Al(4) atoms. There are a spread of Al(3)-Al(4) bond distances ranging from 1.96-3.07 Å. In the fourth Al site, Al(4) is bonded in a distorted hexagonal planar geometry to one Ti(2), one Ti(3), one Al(1), and three equivalent Al(3) atoms.