data_NaAl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.84
_cell_length_b   5.84
_cell_length_c   8.1
_cell_angle_alpha   109.44
_cell_angle_beta   109.44
_cell_angle_gamma   29.3
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaAl2
_chemical_formula_sum   'Na2 Al4'
_cell_volume   126.68
_cell_formula_units_Z   2
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
  Na  Na4  1  0.11  0.0  0.71  1.0
  Na  Na5  1  0.39  0.0  0.89  1.0
  Al  Al0  1  0.24  0.0  0.88  1.0
  Al  Al1  1  0.33  0.0  0.06  1.0
  Al  Al2  1  0.18  0.0  0.55  1.0
  Al  Al3  1  0.27  0.0  0.72  1.0

data_NaAl2
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.95
_cell_length_b   5.84
_cell_length_c   8.1
_cell_angle_alpha   109.44
_cell_angle_beta   90.0
_cell_angle_gamma   104.65
_symmetry_Int_Tables_number   2
_chemical_formula_structural   NaAl2
_chemical_formula_sum   'Na2 Al4'
_cell_volume   126.68
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  Na  Na0  2  0.0  0.36  0.91  1.0
  Al  Al1  2  0.0  0.42  0.75  1.0
  Al  Al2  2  0.0  0.48  0.08  1.0

Na Na Al Al Al Al
NaAl2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two NaAl2 clusters. Na(1) is bonded in a single-bond geometry to one Al(1) and one Al(2) atom. The Na(1)-Al(1) bond length is 0.91 Å. The Na(1)-Al(2) bond length is 1.51 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a single-bond geometry to one Na(1) and one Al(2) atom. The Al(1)-Al(2) bond length is 1.34 Å. In the second Al site, Al(2) is bonded in a 2-coordinate geometry to one Na(1) and one Al(1) atom.