The crystal structure described by Ti3Nb(AlC)2 is H-Phase-derived structured and crystallizes in the trigonal P3m1 space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(1) atoms. In the second Ti site, Ti(2) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(2) atoms. In the third Ti site, Ti(3) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(2) atoms. Nb(1) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Ti(1), three equivalent Ti(2), and six equivalent Al(1) atoms to form distorted AlTi6Al6 cuboctahedra that share corners with six equivalent Al(1)Ti6Al6 cuboctahedra, corners with three equivalent C(1)Ti3Nb3 octahedra, corners with three equivalent C(2)Ti6 octahedra, edges with six equivalent Al(1)Ti6Al6 cuboctahedra, edges with three equivalent C(1)Ti3Nb3 octahedra, edges with three equivalent C(2)Ti6 octahedra, and faces with six equivalent Al(1)Ti6Al6 cuboctahedra. The corner-sharing octahedral tilt angles range from 19-20°. In the second Al site, Al(2) is bonded to three equivalent Ti(3), three equivalent Nb(1), and six equivalent Al(2) atoms to form distorted AlTi3Nb3Al6 cuboctahedra that share corners with six equivalent Al(2)Ti3Nb3Al6 cuboctahedra, corners with three equivalent C(1)Ti3Nb3 octahedra, corners with three equivalent C(2)Ti6 octahedra, edges with six equivalent Al(2)Ti3Nb3Al6 cuboctahedra, edges with three equivalent C(1)Ti3Nb3 octahedra, edges with three equivalent C(2)Ti6 octahedra, and faces with six equivalent Al(2)Ti3Nb3Al6 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. There are two inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Ti(1) and three equivalent Nb(1) atoms to form CTi3Nb3 octahedra that share corners with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, corners with three equivalent Al(1)Ti6Al6 cuboctahedra, edges with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, edges with three equivalent Al(1)Ti6Al6 cuboctahedra, and edges with six equivalent C(1)Ti3Nb3 octahedra. In the second C site, C(2) is bonded to three equivalent Ti(2) and three equivalent Ti(3) atoms to form CTi6 octahedra that share corners with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, corners with three equivalent Al(1)Ti6Al6 cuboctahedra, edges with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, edges with three equivalent Al(1)Ti6Al6 cuboctahedra, and edges with six equivalent C(2)Ti6 octahedra. is represented by the CIF file [CIF]
data_Ti3Nb(AlC)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.068
_cell_length_b   3.068
_cell_length_c   13.861
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   112.983
_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  0.333  0.667  0.586  1.0
  Ti  Ti1  1  0.333  0.667  0.916  1.0
  Ti  Ti2  1  0.667  0.333  0.083  1.0
  Nb  Nb3  1  0.667  0.333  0.411  1.0
  Al  Al4  1  0.667  0.333  0.752  1.0
  Al  Al5  1  0.333  0.667  0.247  1.0
  C  C6  1  0.000  0.000  0.505  1.0
  C  C7  1  0.000  0.000  1.000  1.0
[/CIF]
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The crystal structure described by Ti3Nb(AlC)2 is H-Phase-derived structured and crystallizes in the trigonal P3m1 space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(1) atoms. In the second Ti site, Ti(2) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(2) atoms. In the third Ti site, Ti(3) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(2) atoms. Nb(1) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Ti(1), three equivalent Ti(2), and six equivalent Al(1) atoms to form distorted AlTi6Al6 cuboctahedra that share corners with six equivalent Al(1)Ti6Al6 cuboctahedra, corners with three equivalent C(1)Ti3Nb3 octahedra, corners with three equivalent C(2)Ti6 octahedra, edges with six equivalent Al(1)Ti6Al6 cuboctahedra, edges with three equivalent C(1)Ti3Nb3 octahedra, edges with three equivalent C(2)Ti6 octahedra, and faces with six equivalent Al(1)Ti6Al6 cuboctahedra. The corner-sharing octahedral tilt angles range from 19-20°. In the second Al site, Al(2) is bonded to three equivalent Ti(3), three equivalent Nb(1), and six equivalent Al(2) atoms to form distorted AlTi3Nb3Al6 cuboctahedra that share corners with six equivalent Al(2)Ti3Nb3Al6 cuboctahedra, corners with three equivalent C(1)Ti3Nb3 octahedra, corners with three equivalent C(2)Ti6 octahedra, edges with six equivalent Al(2)Ti3Nb3Al6 cuboctahedra, edges with three equivalent C(1)Ti3Nb3 octahedra, edges with three equivalent C(2)Ti6 octahedra, and faces with six equivalent Al(2)Ti3Nb3Al6 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. There are two inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Ti(1) and three equivalent Nb(1) atoms to form CTi3Nb3 octahedra that share corners with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, corners with three equivalent Al(1)Ti6Al6 cuboctahedra, edges with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, edges with three equivalent Al(1)Ti6Al6 cuboctahedra, and edges with six equivalent C(1)Ti3Nb3 octahedra. In the second C site, C(2) is bonded to three equivalent Ti(2) and three equivalent Ti(3) atoms to form CTi6 octahedra that share corners with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, corners with three equivalent Al(1)Ti6Al6 cuboctahedra, edges with three equivalent Al(2)Ti3Nb3Al6 cuboctahedra, edges with three equivalent Al(1)Ti6Al6 cuboctahedra, and edges with six equivalent C(2)Ti6 octahedra. is represented by the CIF file [CIF]
data_Ti3Nb(AlC)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.068
_cell_length_b   3.068
_cell_length_c   13.861
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   112.983
_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  0.333  0.667  0.586  1.0
  Ti  Ti1  1  0.333  0.667  0.916  1.0
  Ti  Ti2  1  0.667  0.333  0.083  1.0
  Nb  Nb3  1  0.667  0.333  0.411  1.0
  Al  Al4  1  0.667  0.333  0.752  1.0
  Al  Al5  1  0.333  0.667  0.247  1.0
  C  C6  1  0.000  0.000  0.505  1.0
  C  C7  1  0.000  0.000  1.000  1.0
[/CIF]
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