data_AlB4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.06
_cell_length_b   4.06
_cell_length_c   4.06
_cell_angle_alpha   109.47
_cell_angle_beta   109.47
_cell_angle_gamma   109.47
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AlB4
_chemical_formula_sum   'Al1 B4'
_cell_volume   51.66
_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
  B  B1  1  0.17  0.17  0.83  1.0
  B  B2  1  0.83  0.17  0.17  1.0
  B  B3  1  0.17  0.17  0.17  1.0
  B  B4  1  0.17  0.83  0.17  1.0

data_AlB4
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.64
_cell_length_b   6.64
_cell_length_c   4.06
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   AlB4
_chemical_formula_sum   'Al3 B12'
_cell_volume   154.98
_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+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+1/3, z+1/3'
  10  '-y+2/3, -x+1/3, z+1/3'
  11  '-x+y+2/3, y+1/3, z+1/3'
  12  'x+2/3, x-y+1/3, z+1/3'
  13  'x+1/3, y+2/3, z+2/3'
  14  '-y+1/3, x-y+2/3, z+2/3'
  15  '-x+y+1/3, -x+2/3, z+2/3'
  16  '-y+1/3, -x+2/3, z+2/3'
  17  '-x+y+1/3, y+2/3, z+2/3'
  18  'x+1/3, x-y+2/3, z+2/3'
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  3  0.0  0.0  0.0  1.0
  B  B1  9  0.1  0.55  0.72  1.0
  B  B2  3  0.0  0.0  0.17  1.0

Al B B B B
Al B B B B 0 3 o o o 0 1 o o - 0 2 - o o 0 4 o - o 1 3 o o + 2 3 + o o 3 4 o - o 
AlB4 is Tungsten structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three AlB4 clusters. Al(1) is bonded in a single-bond geometry to one B(2) and three equivalent B(1) atoms. The Al(1)-B(2) bond length is 0.70 Å. All Al(1)-B(1) bond lengths are 1.35 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a distorted single-bond geometry to one Al(1) and one B(2) atom. The B(1)-B(2) bond length is 1.41 Å. In the second B site, B(2) is bonded in a single-bond geometry to one Al(1) and three equivalent B(1) atoms.