data_SrGa3I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.81
_cell_length_b   5.81
_cell_length_c   5.81
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrGa3I
_chemical_formula_sum   'Sr1 Ga3 I1'
_cell_volume   196.62
_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
  Sr  Sr1  1  0.0  0.0  0.0  1.0
  Ga  Ga2  1  0.91  0.0  0.91  1.0
  Ga  Ga3  1  0.91  0.91  0.0  1.0
  Ga  Ga4  1  0.0  0.91  0.91  1.0
  I  I0  1  0.91  0.91  0.91  1.0

data_SrGa3I
_symmetry_space_group_name_H-M   R3m
_cell_length_a   8.22
_cell_length_b   8.22
_cell_length_c   10.07
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SrGa3I
_chemical_formula_sum   'Sr3 Ga9 I3'
_cell_volume   589.85
_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
  Sr  Sr0  3  0.0  0.0  0.0  1.0
  Ga  Ga1  9  0.06  0.03  0.94  1.0
  I  I2  3  0.0  0.0  0.91  1.0

Sr Ga Ga Ga I
Sr Ga Ga Ga I 0 2 - - o 0 1 - o - 0 3 o - - 1 4 o - o 2 4 o o - 3 4 - o o 
SrGa3I is alpha Po structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three SrGa3I clusters. Sr(1) is bonded in a 3-coordinate geometry to three equivalent Ga(1) atoms. All Sr(1)-Ga(1) bond lengths are 0.76 Å. Ga(1) is bonded in a distorted L-shaped geometry to one Sr(1) and one I(1) atom. The Ga(1)-I(1) bond length is 0.54 Å. I(1) is bonded in a distorted T-shaped geometry to three equivalent Ga(1) atoms.