The compound described by Ti4(NbAl3)3 is alpha La-derived structured and crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to four equivalent Nb(2) and eight equivalent Al(2) atoms to form TiNb4Al8 cuboctahedra that share corners with four equivalent Ti(1)Nb4Al8 cuboctahedra, corners with eight equivalent Nb(1)Ti4Al8 cuboctahedra, edges with eight equivalent Ti(3)Nb2Al10 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Al(1)Ti4Al8 cuboctahedra, faces with four equivalent Ti(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the second Ti site, Ti(2) is bonded to four equivalent Nb(2) and eight equivalent Al(2) atoms to form TiNb4Al8 cuboctahedra that share corners with four equivalent Ti(2)Nb4Al8 cuboctahedra, corners with eight equivalent Al(1)Ti4Al8 cuboctahedra, edges with eight equivalent Ti(3)Nb2Al10 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Nb(1)Ti4Al8 cuboctahedra, faces with four equivalent Ti(1)Nb4Al8 cuboctahedra, faces with four equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the third Ti site, Ti(3) is bonded to two equivalent Nb(1), two equivalent Al(1), and eight equivalent Al(2) atoms to form TiNb2Al10 cuboctahedra that share corners with four equivalent Ti(3)Nb2Al10 cuboctahedra, corners with eight equivalent Nb(2)Ti4Al8 cuboctahedra, edges with four equivalent Ti(1)Nb4Al8 cuboctahedra, edges with four equivalent Ti(2)Nb4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Nb(1)Ti4Al8 cuboctahedra, faces with two equivalent Nb(2)Ti4Al8 cuboctahedra, faces with two equivalent Al(1)Ti4Al8 cuboctahedra, faces with four equivalent Ti(3)Nb2Al10 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to four equivalent Ti(3) and eight equivalent Al(2) atoms to form NbTi4Al8 cuboctahedra that share corners with four equivalent Nb(1)Ti4Al8 cuboctahedra, corners with eight equivalent Ti(1)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(2)Ti4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Ti(2)Nb4Al8 cuboctahedra, faces with four equivalent Ti(3)Nb2Al10 cuboctahedra, faces with four equivalent Al(1)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the second Nb site, Nb(2) is bonded to two equivalent Ti(1), two equivalent Ti(2), and eight equivalent Al(2) atoms to form NbTi4Al8 cuboctahedra that share corners with four equivalent Nb(2)Ti4Al8 cuboctahedra, corners with eight equivalent Ti(3)Nb2Al10 cuboctahedra, edges with four equivalent Nb(1)Ti4Al8 cuboctahedra, edges with four equivalent Al(1)Ti4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Ti(3)Nb2Al10 cuboctahedra, faces with two equivalent Ti(1)Nb4Al8 cuboctahedra, faces with two equivalent Ti(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Ti(3) and eight equivalent Al(2) atoms to form AlTi4Al8 cuboctahedra that share corners with four equivalent Al(1)Ti4Al8 cuboctahedra, corners with eight equivalent Ti(2)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(2)Ti4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Ti(1)Nb4Al8 cuboctahedra, faces with four equivalent Ti(3)Nb2Al10 cuboctahedra, faces with four equivalent Nb(1)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the second Al site, Al(2) is bonded to one Ti(1), one Ti(2), two equivalent Ti(3), one Nb(1), two equivalent Nb(2), one Al(1), and four equivalent Al(2) atoms to form AlTi4Nb3Al5 cuboctahedra that share corners with twelve equivalent Al(2)Ti4Nb3Al5 cuboctahedra, edges with two equivalent Ti(1)Nb4Al8 cuboctahedra, edges with two equivalent Ti(2)Nb4Al8 cuboctahedra, edges with two equivalent Nb(1)Ti4Al8 cuboctahedra, edges with two equivalent Al(1)Ti4Al8 cuboctahedra, edges with four equivalent Ti(3)Nb2Al10 cuboctahedra, edges with four equivalent Nb(2)Ti4Al8 cuboctahedra, edges with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra,  a faceface with one Ti(1)Nb4Al8 cuboctahedra,  a faceface with one Ti(2)Nb4Al8 cuboctahedra,  a faceface with one Nb(1)Ti4Al8 cuboctahedra,  a faceface with one Al(1)Ti4Al8 cuboctahedra, faces with two equivalent Ti(3)Nb2Al10 cuboctahedra, faces with two equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with ten equivalent Al(2)Ti4Nb3Al5 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ti4(NbAl3)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.678
_cell_length_b   5.678
_cell_length_c   8.166
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   263.251
_cell_formula_units_Z   1
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  0.500  0.500  0.000  1.0
  Ti  Ti1  1  0.000  0.000  0.000  1.0
  Ti  Ti2  1  0.000  0.500  0.500  1.0
  Ti  Ti3  1  0.500  0.000  0.500  1.0
  Nb  Nb4  1  0.000  0.000  0.500  1.0
  Nb  Nb5  1  0.000  0.500  0.000  1.0
  Nb  Nb6  1  0.500  0.000  0.000  1.0
  Al  Al7  1  0.500  0.500  0.500  1.0
  Al  Al8  1  0.249  0.249  0.250  1.0
  Al  Al9  1  0.751  0.751  0.750  1.0
  Al  Al10  1  0.751  0.751  0.250  1.0
  Al  Al11  1  0.751  0.249  0.250  1.0
  Al  Al12  1  0.751  0.249  0.750  1.0
  Al  Al13  1  0.249  0.249  0.750  1.0
  Al  Al14  1  0.249  0.751  0.750  1.0
  Al  Al15  1  0.249  0.751  0.250  1.0
[/CIF]
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The compound described by Ti4(NbAl3)3 is alpha La-derived structured and crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to four equivalent Nb(2) and eight equivalent Al(2) atoms to form TiNb4Al8 cuboctahedra that share corners with four equivalent Ti(1)Nb4Al8 cuboctahedra, corners with eight equivalent Nb(1)Ti4Al8 cuboctahedra, edges with eight equivalent Ti(3)Nb2Al10 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Al(1)Ti4Al8 cuboctahedra, faces with four equivalent Ti(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the second Ti site, Ti(2) is bonded to four equivalent Nb(2) and eight equivalent Al(2) atoms to form TiNb4Al8 cuboctahedra that share corners with four equivalent Ti(2)Nb4Al8 cuboctahedra, corners with eight equivalent Al(1)Ti4Al8 cuboctahedra, edges with eight equivalent Ti(3)Nb2Al10 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Nb(1)Ti4Al8 cuboctahedra, faces with four equivalent Ti(1)Nb4Al8 cuboctahedra, faces with four equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the third Ti site, Ti(3) is bonded to two equivalent Nb(1), two equivalent Al(1), and eight equivalent Al(2) atoms to form TiNb2Al10 cuboctahedra that share corners with four equivalent Ti(3)Nb2Al10 cuboctahedra, corners with eight equivalent Nb(2)Ti4Al8 cuboctahedra, edges with four equivalent Ti(1)Nb4Al8 cuboctahedra, edges with four equivalent Ti(2)Nb4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Nb(1)Ti4Al8 cuboctahedra, faces with two equivalent Nb(2)Ti4Al8 cuboctahedra, faces with two equivalent Al(1)Ti4Al8 cuboctahedra, faces with four equivalent Ti(3)Nb2Al10 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to four equivalent Ti(3) and eight equivalent Al(2) atoms to form NbTi4Al8 cuboctahedra that share corners with four equivalent Nb(1)Ti4Al8 cuboctahedra, corners with eight equivalent Ti(1)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(2)Ti4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Ti(2)Nb4Al8 cuboctahedra, faces with four equivalent Ti(3)Nb2Al10 cuboctahedra, faces with four equivalent Al(1)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the second Nb site, Nb(2) is bonded to two equivalent Ti(1), two equivalent Ti(2), and eight equivalent Al(2) atoms to form NbTi4Al8 cuboctahedra that share corners with four equivalent Nb(2)Ti4Al8 cuboctahedra, corners with eight equivalent Ti(3)Nb2Al10 cuboctahedra, edges with four equivalent Nb(1)Ti4Al8 cuboctahedra, edges with four equivalent Al(1)Ti4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Ti(3)Nb2Al10 cuboctahedra, faces with two equivalent Ti(1)Nb4Al8 cuboctahedra, faces with two equivalent Ti(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Ti(3) and eight equivalent Al(2) atoms to form AlTi4Al8 cuboctahedra that share corners with four equivalent Al(1)Ti4Al8 cuboctahedra, corners with eight equivalent Ti(2)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(2)Ti4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Ti4Nb3Al5 cuboctahedra, faces with two equivalent Ti(1)Nb4Al8 cuboctahedra, faces with four equivalent Ti(3)Nb2Al10 cuboctahedra, faces with four equivalent Nb(1)Ti4Al8 cuboctahedra, and faces with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra. In the second Al site, Al(2) is bonded to one Ti(1), one Ti(2), two equivalent Ti(3), one Nb(1), two equivalent Nb(2), one Al(1), and four equivalent Al(2) atoms to form AlTi4Nb3Al5 cuboctahedra that share corners with twelve equivalent Al(2)Ti4Nb3Al5 cuboctahedra, edges with two equivalent Ti(1)Nb4Al8 cuboctahedra, edges with two equivalent Ti(2)Nb4Al8 cuboctahedra, edges with two equivalent Nb(1)Ti4Al8 cuboctahedra, edges with two equivalent Al(1)Ti4Al8 cuboctahedra, edges with four equivalent Ti(3)Nb2Al10 cuboctahedra, edges with four equivalent Nb(2)Ti4Al8 cuboctahedra, edges with eight equivalent Al(2)Ti4Nb3Al5 cuboctahedra,  a faceface with one Ti(1)Nb4Al8 cuboctahedra,  a faceface with one Ti(2)Nb4Al8 cuboctahedra,  a faceface with one Nb(1)Ti4Al8 cuboctahedra,  a faceface with one Al(1)Ti4Al8 cuboctahedra, faces with two equivalent Ti(3)Nb2Al10 cuboctahedra, faces with two equivalent Nb(2)Ti4Al8 cuboctahedra, and faces with ten equivalent Al(2)Ti4Nb3Al5 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ti4(NbAl3)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.678
_cell_length_b   5.678
_cell_length_c   8.166
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   263.251
_cell_formula_units_Z   1
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  0.500  0.500  0.000  1.0
  Ti  Ti1  1  0.000  0.000  0.000  1.0
  Ti  Ti2  1  0.000  0.500  0.500  1.0
  Ti  Ti3  1  0.500  0.000  0.500  1.0
  Nb  Nb4  1  0.000  0.000  0.500  1.0
  Nb  Nb5  1  0.000  0.500  0.000  1.0
  Nb  Nb6  1  0.500  0.000  0.000  1.0
  Al  Al7  1  0.500  0.500  0.500  1.0
  Al  Al8  1  0.249  0.249  0.250  1.0
  Al  Al9  1  0.751  0.751  0.750  1.0
  Al  Al10  1  0.751  0.751  0.250  1.0
  Al  Al11  1  0.751  0.249  0.250  1.0
  Al  Al12  1  0.751  0.249  0.750  1.0
  Al  Al13  1  0.249  0.249  0.750  1.0
  Al  Al14  1  0.249  0.751  0.750  1.0
  Al  Al15  1  0.249  0.751  0.250  1.0
[/CIF]
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