data_Nb3Al
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.82
_cell_length_b   2.82
_cell_length_c   9.11
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   104.67
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Nb3Al
_chemical_formula_sum   'Nb3 Al1'
_cell_volume   70.03
_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  Nb1  1  0.72  0.0  0.91  1.0
  Nb  Nb2  1  0.0  0.0  0.56  1.0
  Nb  Nb3  1  0.72  0.0  0.2  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0

data_Nb3Al
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.82
_cell_length_b   2.82
_cell_length_c   9.11
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   104.67
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Nb3Al
_chemical_formula_sum   'Nb3 Al1'
_cell_volume   70.03
_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  0.0  0.0  0.56  1.0
  Nb  Nb1  1  0.72  0.0  0.2  1.0
  Nb  Nb2  1  0.72  0.0  0.91  1.0
  Al  Al3  1  0.0  0.0  0.0  1.0

Nb Nb Nb Al
Nb3Al crystallizes in the triclinic P1 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a distorted single-bond geometry to one Nb(2) and one Al(1) atom. The Nb(1)-Nb(2) bond length is 3.30 Å. The Nb(1)-Al(1) bond length is 1.15 Å. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one Nb(1), one Nb(3), and four equivalent Nb(2) atoms. The Nb(2)-Nb(3) bond length is 3.30 Å. All Nb(2)-Nb(2) bond lengths are 2.82 Å. In the third Nb site, Nb(3) is bonded in a distorted single-bond geometry to one Nb(2) and one Al(1) atom. The Nb(3)-Al(1) bond length is 2.02 Å. Al(1) is bonded in a distorted single-bond geometry to one Nb(1) and one Nb(3) atom.