data_Al2SiBr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   3.13
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Al2SiBr
_chemical_formula_sum   'Al2 Si1 Br1'
_cell_volume   75.87
_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  0.46  0.57  1.0
  Al  Al1  1  0.46  0.0  0.57  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0
  Br  Br2  1  0.46  0.46  0.0  1.0

data_Al2SiBr
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.96
_cell_length_b   6.96
_cell_length_c   3.13
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Al2SiBr
_chemical_formula_sum   'Al4 Si2 Br2'
_cell_volume   151.73
_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  4  0.23  0.23  0.57  1.0
  Si  Si1  2  0.0  0.0  0.0  1.0
  Br  Br2  2  0.46  0.0  -0.0  1.0

Al Al Si Br
Al Al Si Br 0 3 - o o 0 3 - o + 0 3 o o o 0 3 o o + 0 2 o o o 0 2 o o + 0 2 o + o 0 2 o + + 0 1 o o o 0 0 o o + 1 2 o o o 1 2 o o + 1 2 + o o 1 2 + o + 1 3 o - o 1 3 o - + 1 3 o o o 1 3 o o + 1 1 o o + 2 2 o o + 2 3 o o o 3 3 o o + 
Al2SiBr crystallizes in the monoclinic Cm space group. Al(1) is bonded in a 4-coordinate geometry to three equivalent Si(1) and three equivalent Br(1) atoms. There are a spread of Al(1)-Si(1) bond distances ranging from 2.64-2.98 Å. There are a spread of Al(1)-Br(1) bond distances ranging from 2.64-2.98 Å. Si(1) is bonded in a 6-coordinate geometry to six equivalent Al(1) atoms. Br(1) is bonded in a 6-coordinate geometry to six equivalent Al(1) atoms.