data_Lu3Al
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.84
_cell_length_b   5.84
_cell_length_c   5.84
_cell_angle_alpha   134.02
_cell_angle_beta   134.02
_cell_angle_gamma   67.06
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Lu3Al
_chemical_formula_sum   'Lu3 Al1'
_cell_volume   101.3
_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
  Lu  Lu1  1  0.0  0.0  0.87  1.0
  Lu  Lu2  1  0.0  0.28  0.43  1.0
  Lu  Lu3  1  0.28  0.0  0.43  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0

data_Lu3Al
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.45
_cell_length_b   6.45
_cell_length_c   5.84
_cell_angle_alpha   90.0
_cell_angle_beta   123.53
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Lu3Al
_chemical_formula_sum   'Lu6 Al2'
_cell_volume   202.6
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Lu  Lu0  4  0.36  0.36  0.15  1.0
  Lu  Lu1  2  0.0  0.0  0.87  1.0
  Al  Al2  2  0.0  0.0  0.0  1.0

Lu Lu Lu Al
Lu3Al crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Lu3Al clusters. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded in a single-bond geometry to one Al(1) atom. The Lu(1)-Al(1) bond length is 0.77 Å. In the second Lu site, Lu(2) is bonded in a distorted single-bond geometry to one Al(1) atom. The Lu(2)-Al(1) bond length is 1.83 Å. Al(1) is bonded in a distorted single-bond geometry to one Lu(1) and two equivalent Lu(2) atoms.