data_Al3Mo
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.41
_cell_length_b   3.41
_cell_length_c   5.4
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Al3Mo
_chemical_formula_sum   'Al3 Mo1'
_cell_volume   62.82
_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
  Al  Al0  1  0.71  0.71  0.99  1.0
  Al  Al1  1  0.0  0.0  0.0  1.0
  Al  Al2  1  0.71  0.71  0.41  1.0
  Mo  Mo3  1  0.0  0.0  0.7  1.0

data_Al3Mo
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.82
_cell_length_b   4.82
_cell_length_c   5.4
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Al3Mo
_chemical_formula_sum   'Al6 Mo2'
_cell_volume   125.64
_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
  Al  Al0  2  0.0  0.0  0.0  1.0
  Al  Al1  2  0.21  0.5  0.41  1.0
  Al  Al2  2  0.21  0.5  0.99  1.0
  Mo  Mo3  2  0.0  0.0  0.7  1.0

Al Al Al Mo
Al Al Al Mo 0 1 + + + 0 2 o o + 1 3 o o - 2 3 + + o 
MoAl3 crystallizes in the monoclinic Cm space group. Mo(1) is bonded in a 2-coordinate geometry to one Al(2), one Al(3), and three equivalent Al(1) atoms. The Mo(1)-Al(2) bond length is 1.62 Å. The Mo(1)-Al(3) bond length is 2.12 Å. There is one shorter (2.12 Å) and two longer (3.05 Å) Mo(1)-Al(1) bond lengths. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a 7-coordinate geometry to three equivalent Mo(1), one Al(3), and three equivalent Al(2) atoms. The Al(1)-Al(3) bond length is 2.25 Å. There is one shorter (1.42 Å) and two longer (2.61 Å) Al(1)-Al(2) bond lengths. In the second Al site, Al(2) is bonded in a distorted L-shaped geometry to one Mo(1) and three equivalent Al(1) atoms. In the third Al site, Al(3) is bonded in a distorted single-bond geometry to one Mo(1) and one Al(1) atom.