The structure described by Nb3Fe8Al is Hexagonal Laves-derived structured and crystallizes in the trigonal P3m1 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Fe(1), three equivalent Fe(3), six equivalent Fe(4), and three equivalent Al(1) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(3), three equivalent Fe(2), three equivalent Fe(3), and six equivalent Fe(4) atoms. In the third Nb site, Nb(3) is bonded in a 16-coordinate geometry to three equivalent Nb(2), three equivalent Fe(2), three equivalent Fe(4), six equivalent Fe(3), and one Al(1) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Nb(1), three equivalent Fe(3), three equivalent Fe(4), and three equivalent Al(1) atoms to form FeNb3Al3Fe6 cuboctahedra that share corners with six equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, corners with six equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with six equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with two equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with nine equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, and faces with nine equivalent Fe(4)Nb5AlFe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to three equivalent Nb(2), three equivalent Nb(3), three equivalent Fe(3), and three equivalent Fe(4) atoms to form FeNb6Fe6 cuboctahedra that share corners with six equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, corners with six equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with six equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with two equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with nine equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, and faces with nine equivalent Fe(4)Nb5AlFe6 cuboctahedra. In the third Fe site, Fe(3) is bonded to one Nb(1), one Nb(2), two equivalent Nb(3), one Fe(1), one Fe(2), four equivalent Fe(3), and two equivalent Al(1) atoms to form FeNb4Al2Fe6 cuboctahedra that share corners with two equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, corners with two equivalent Fe(2)Nb6Fe6 cuboctahedra, corners with four equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, corners with ten equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with two equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, edges with four equivalent Fe(4)Nb5AlFe6 cuboctahedra, faces with three equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with three equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with four equivalent Fe(4)Nb5AlFe6 cuboctahedra, and faces with eight equivalent Fe(3)Nb4Al2Fe6 cuboctahedra. In the fourth Fe site, Fe(4) is bonded to one Nb(3), two equivalent Nb(1), two equivalent Nb(2), one Fe(1), one Fe(2), four equivalent Fe(4), and one Al(1) atom to form FeNb5AlFe6 cuboctahedra that share corners with two equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, corners with two equivalent Fe(2)Nb6Fe6 cuboctahedra, corners with four equivalent Fe(4)Nb5AlFe6 cuboctahedra, corners with ten equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, edges with two equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with four equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, faces with three equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with three equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with four equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, and faces with eight equivalent Fe(4)Nb5AlFe6 cuboctahedra. Al(1) is bonded in a 16-coordinate geometry to one Nb(3), three equivalent Nb(1), three equivalent Fe(1), three equivalent Fe(4), and six equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_Nb3AlFe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.740
_cell_length_b   4.743
_cell_length_c   7.893
_cell_angle_alpha   90.000
_cell_angle_beta   90.030
_cell_angle_gamma   59.982
_symmetry_Int_Tables_number   1
_cell_volume   153.662
_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  0.667  0.667  0.440  1.0
  Nb  Nb1  1  0.667  0.667  0.068  1.0
  Nb  Nb2  1  0.334  0.333  0.923  1.0
  Al  Al3  1  0.334  0.333  0.560  1.0
  Fe  Fe4  1  1.000  0.000  0.502  1.0
  Fe  Fe5  1  1.000  0.000  0.007  1.0
  Fe  Fe6  1  0.831  0.338  0.748  1.0
  Fe  Fe7  1  0.338  0.831  0.748  1.0
  Fe  Fe8  1  0.831  0.831  0.748  1.0
  Fe  Fe9  1  0.170  0.660  0.252  1.0
  Fe  Fe10  1  0.660  0.170  0.252  1.0
  Fe  Fe11  1  0.170  0.170  0.252  1.0
[/CIF]
.
The structure described by Nb3Fe8Al is Hexagonal Laves-derived structured and crystallizes in the trigonal P3m1 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Fe(1), three equivalent Fe(3), six equivalent Fe(4), and three equivalent Al(1) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(3), three equivalent Fe(2), three equivalent Fe(3), and six equivalent Fe(4) atoms. In the third Nb site, Nb(3) is bonded in a 16-coordinate geometry to three equivalent Nb(2), three equivalent Fe(2), three equivalent Fe(4), six equivalent Fe(3), and one Al(1) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Nb(1), three equivalent Fe(3), three equivalent Fe(4), and three equivalent Al(1) atoms to form FeNb3Al3Fe6 cuboctahedra that share corners with six equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, corners with six equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with six equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with two equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with nine equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, and faces with nine equivalent Fe(4)Nb5AlFe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to three equivalent Nb(2), three equivalent Nb(3), three equivalent Fe(3), and three equivalent Fe(4) atoms to form FeNb6Fe6 cuboctahedra that share corners with six equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, corners with six equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with six equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with two equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with nine equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, and faces with nine equivalent Fe(4)Nb5AlFe6 cuboctahedra. In the third Fe site, Fe(3) is bonded to one Nb(1), one Nb(2), two equivalent Nb(3), one Fe(1), one Fe(2), four equivalent Fe(3), and two equivalent Al(1) atoms to form FeNb4Al2Fe6 cuboctahedra that share corners with two equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, corners with two equivalent Fe(2)Nb6Fe6 cuboctahedra, corners with four equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, corners with ten equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with two equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, edges with four equivalent Fe(4)Nb5AlFe6 cuboctahedra, faces with three equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with three equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with four equivalent Fe(4)Nb5AlFe6 cuboctahedra, and faces with eight equivalent Fe(3)Nb4Al2Fe6 cuboctahedra. In the fourth Fe site, Fe(4) is bonded to one Nb(3), two equivalent Nb(1), two equivalent Nb(2), one Fe(1), one Fe(2), four equivalent Fe(4), and one Al(1) atom to form FeNb5AlFe6 cuboctahedra that share corners with two equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, corners with two equivalent Fe(2)Nb6Fe6 cuboctahedra, corners with four equivalent Fe(4)Nb5AlFe6 cuboctahedra, corners with ten equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, edges with two equivalent Fe(4)Nb5AlFe6 cuboctahedra, edges with four equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, faces with three equivalent Fe(1)Nb3Al3Fe6 cuboctahedra, faces with three equivalent Fe(2)Nb6Fe6 cuboctahedra, faces with four equivalent Fe(3)Nb4Al2Fe6 cuboctahedra, and faces with eight equivalent Fe(4)Nb5AlFe6 cuboctahedra. Al(1) is bonded in a 16-coordinate geometry to one Nb(3), three equivalent Nb(1), three equivalent Fe(1), three equivalent Fe(4), and six equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_Nb3AlFe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.740
_cell_length_b   4.743
_cell_length_c   7.893
_cell_angle_alpha   90.000
_cell_angle_beta   90.030
_cell_angle_gamma   59.982
_symmetry_Int_Tables_number   1
_cell_volume   153.662
_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  0.667  0.667  0.440  1.0
  Nb  Nb1  1  0.667  0.667  0.068  1.0
  Nb  Nb2  1  0.334  0.333  0.923  1.0
  Al  Al3  1  0.334  0.333  0.560  1.0
  Fe  Fe4  1  1.000  0.000  0.502  1.0
  Fe  Fe5  1  1.000  0.000  0.007  1.0
  Fe  Fe6  1  0.831  0.338  0.748  1.0
  Fe  Fe7  1  0.338  0.831  0.748  1.0
  Fe  Fe8  1  0.831  0.831  0.748  1.0
  Fe  Fe9  1  0.170  0.660  0.252  1.0
  Fe  Fe10  1  0.660  0.170  0.252  1.0
  Fe  Fe11  1  0.170  0.170  0.252  1.0
[/CIF]
.