data_Al5Ge
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.34
_cell_length_b   5.34
_cell_length_c   5.34
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Al5Ge
_chemical_formula_sum   'Al5 Ge1'
_cell_volume   107.61
_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  0.0  0.0  0.0  1.0
  Al  Al1  1  0.83  0.83  0.83  1.0
  Al  Al2  1  0.72  0.83  0.72  1.0
  Al  Al3  1  0.72  0.72  0.83  1.0
  Al  Al4  1  0.83  0.72  0.72  1.0
  Ge  Ge5  1  0.66  0.66  0.66  1.0

data_Al5Ge
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.34
_cell_length_b   5.34
_cell_length_c   13.08
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Al5Ge
_chemical_formula_sum   'Al15 Ge3'
_cell_volume   322.82
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  9  0.04  0.07  0.24  1.0
  Al  Al1  3  0.0  0.0  0.0  1.0
  Al  Al2  3  0.0  0.0  0.17  1.0
  Ge  Ge3  3  0.0  0.0  0.34  1.0

Al Al Al Al Al Ge
Al Al Al Al Al Ge 0 1 - - - 1 4 o o o 1 3 o o o 1 2 o o o 2 3 o o o 2 4 o o o 2 5 o o o 3 4 o o o 3 5 o o o 4 5 o o o 
Al5Ge crystallizes in the trigonal R3m space group. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one Al(2) and three equivalent Ge(1) atoms to form distorted corner-sharing AlAlGe3 trigonal pyramids. The Al(1)-Al(2) bond length is 2.22 Å. All Al(1)-Ge(1) bond lengths are 3.08 Å. In the second Al site, Al(2) is bonded in a distorted rectangular see-saw-like geometry to one Al(1) and three equivalent Al(3) atoms. All Al(2)-Al(3) bond lengths are 1.02 Å. In the third Al site, Al(3) is bonded in a 2-coordinate geometry to one Al(2), two equivalent Al(3), and one Ge(1) atom. Both Al(3)-Al(3) bond lengths are 0.59 Å. The Al(3)-Ge(1) bond length is 1.28 Å. Ge(1) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent Al(3) atoms.