The compound described by NbAl3 crystallizes in the tetragonal I4/mmm space group. Nb(1) is bonded to four equivalent Al(1) and eight equivalent Al(2) atoms to form NbAl12 cuboctahedra that share corners with four equivalent Nb(1)Al12 cuboctahedra, corners with eight equivalent Al(1)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(1)Al12 cuboctahedra, edges with sixteen equivalent Al(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(1)Al12 cuboctahedra, faces with six equivalent Al(1)Nb4Al8 cuboctahedra, and faces with eight equivalent Al(2)Nb4Al8 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Nb(1) and eight equivalent Al(2) atoms to form AlNb4Al8 cuboctahedra that share corners with four equivalent Al(1)Nb4Al8 cuboctahedra, corners with eight equivalent Nb(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Nb4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Nb4Al8 cuboctahedra, faces with four equivalent Al(1)Nb4Al8 cuboctahedra, faces with six equivalent Nb(1)Al12 cuboctahedra, and faces with eight equivalent Al(2)Nb4Al8 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Nb(1), four equivalent Al(1), and four equivalent Al(2) atoms to form AlNb4Al8 cuboctahedra that share corners with twelve equivalent Al(2)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Nb4Al8 cuboctahedra, edges with eight equivalent Al(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(1)Al12 cuboctahedra, faces with four equivalent Al(1)Nb4Al8 cuboctahedra, and faces with ten equivalent Al(2)Nb4Al8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.834
_cell_length_b   3.834
_cell_length_c   5.077
_cell_angle_alpha   112.185
_cell_angle_beta   112.185
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   63.096
_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
  Nb  Nb0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.500  0.500  0.000  1.0
  Al  Al2  1  0.250  0.750  0.500  1.0
  Al  Al3  1  0.750  0.250  0.500  1.0
[/CIF]
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The compound described by NbAl3 crystallizes in the tetragonal I4/mmm space group. Nb(1) is bonded to four equivalent Al(1) and eight equivalent Al(2) atoms to form NbAl12 cuboctahedra that share corners with four equivalent Nb(1)Al12 cuboctahedra, corners with eight equivalent Al(1)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(1)Al12 cuboctahedra, edges with sixteen equivalent Al(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(1)Al12 cuboctahedra, faces with six equivalent Al(1)Nb4Al8 cuboctahedra, and faces with eight equivalent Al(2)Nb4Al8 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Nb(1) and eight equivalent Al(2) atoms to form AlNb4Al8 cuboctahedra that share corners with four equivalent Al(1)Nb4Al8 cuboctahedra, corners with eight equivalent Nb(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Nb4Al8 cuboctahedra, edges with sixteen equivalent Al(2)Nb4Al8 cuboctahedra, faces with four equivalent Al(1)Nb4Al8 cuboctahedra, faces with six equivalent Nb(1)Al12 cuboctahedra, and faces with eight equivalent Al(2)Nb4Al8 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Nb(1), four equivalent Al(1), and four equivalent Al(2) atoms to form AlNb4Al8 cuboctahedra that share corners with twelve equivalent Al(2)Nb4Al8 cuboctahedra, edges with eight equivalent Nb(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Nb4Al8 cuboctahedra, edges with eight equivalent Al(2)Nb4Al8 cuboctahedra, faces with four equivalent Nb(1)Al12 cuboctahedra, faces with four equivalent Al(1)Nb4Al8 cuboctahedra, and faces with ten equivalent Al(2)Nb4Al8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.834
_cell_length_b   3.834
_cell_length_c   5.077
_cell_angle_alpha   112.185
_cell_angle_beta   112.185
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   63.096
_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
  Nb  Nb0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.500  0.500  0.000  1.0
  Al  Al2  1  0.250  0.750  0.500  1.0
  Al  Al3  1  0.750  0.250  0.500  1.0
[/CIF]
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