The material described by La3(AlI)2 crystallizes in the monoclinic C2/m space group. There are three inequivalent La sites. In the first La site, La(1) is bonded in a 6-coordinate geometry to one Al(1), three equivalent Al(2), and two equivalent I(1) atoms. In the second La site, La(2) is bonded to one Al(1), two equivalent Al(2), one I(1), and three equivalent I(2) atoms to form distorted edge-sharing LaAl3I4 pentagonal bipyramids. In the third La site, La(3) is bonded in a 9-coordinate geometry to two equivalent Al(2), four equivalent Al(1), one I(1), and two equivalent I(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 9-coordinate geometry to one La(1), one La(2), four equivalent La(3), one Al(1), and two equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 9-coordinate geometry to two equivalent La(2), two equivalent La(3), three equivalent La(1), and two equivalent Al(1) atoms. There are two inequivalent I sites. In the first I site, I(1) is bonded in a distorted rectangular see-saw-like geometry to one La(2), one La(3), and two equivalent La(1) atoms. In the second I site, I(2) is bonded to two equivalent La(3) and three equivalent La(2) atoms to form distorted edge-sharing ILa5 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3(AlI)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.192
_cell_length_b   10.192
_cell_length_c   12.478
_cell_angle_alpha   59.239
_cell_angle_beta   59.239
_cell_angle_gamma   24.657
_symmetry_Int_Tables_number   1
_cell_volume   460.708
_cell_formula_units_Z   2
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
  La  La0  1  0.831  0.831  0.392  1.0
  La  La1  1  0.169  0.169  0.608  1.0
  La  La2  1  0.755  0.755  0.802  1.0
  La  La3  1  0.245  0.245  0.198  1.0
  La  La4  1  0.535  0.535  0.309  1.0
  La  La5  1  0.465  0.465  0.691  1.0
  Al  Al6  1  0.927  0.927  0.533  1.0
  Al  Al7  1  0.073  0.073  0.467  1.0
  Al  Al8  1  0.341  0.341  0.585  1.0
  Al  Al9  1  0.659  0.659  0.415  1.0
  I  I10  1  0.423  0.423  0.170  1.0
  I  I11  1  0.577  0.577  0.830  1.0
  I  I12  1  0.858  0.858  0.941  1.0
  I  I13  1  0.142  0.142  0.059  1.0
[/CIF]
.
The material described by La3(AlI)2 crystallizes in the monoclinic C2/m space group. There are three inequivalent La sites. In the first La site, La(1) is bonded in a 6-coordinate geometry to one Al(1), three equivalent Al(2), and two equivalent I(1) atoms. In the second La site, La(2) is bonded to one Al(1), two equivalent Al(2), one I(1), and three equivalent I(2) atoms to form distorted edge-sharing LaAl3I4 pentagonal bipyramids. In the third La site, La(3) is bonded in a 9-coordinate geometry to two equivalent Al(2), four equivalent Al(1), one I(1), and two equivalent I(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 9-coordinate geometry to one La(1), one La(2), four equivalent La(3), one Al(1), and two equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 9-coordinate geometry to two equivalent La(2), two equivalent La(3), three equivalent La(1), and two equivalent Al(1) atoms. There are two inequivalent I sites. In the first I site, I(1) is bonded in a distorted rectangular see-saw-like geometry to one La(2), one La(3), and two equivalent La(1) atoms. In the second I site, I(2) is bonded to two equivalent La(3) and three equivalent La(2) atoms to form distorted edge-sharing ILa5 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3(AlI)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.192
_cell_length_b   10.192
_cell_length_c   12.478
_cell_angle_alpha   59.239
_cell_angle_beta   59.239
_cell_angle_gamma   24.657
_symmetry_Int_Tables_number   1
_cell_volume   460.708
_cell_formula_units_Z   2
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
  La  La0  1  0.831  0.831  0.392  1.0
  La  La1  1  0.169  0.169  0.608  1.0
  La  La2  1  0.755  0.755  0.802  1.0
  La  La3  1  0.245  0.245  0.198  1.0
  La  La4  1  0.535  0.535  0.309  1.0
  La  La5  1  0.465  0.465  0.691  1.0
  Al  Al6  1  0.927  0.927  0.533  1.0
  Al  Al7  1  0.073  0.073  0.467  1.0
  Al  Al8  1  0.341  0.341  0.585  1.0
  Al  Al9  1  0.659  0.659  0.415  1.0
  I  I10  1  0.423  0.423  0.170  1.0
  I  I11  1  0.577  0.577  0.830  1.0
  I  I12  1  0.858  0.858  0.941  1.0
  I  I13  1  0.142  0.142  0.059  1.0
[/CIF]
.