The compound described by Cs3Cr2I9 crystallizes in the trigonal R-3c space group. Cs(1) is bonded to four equivalent I(1) and eight equivalent I(2) atoms to form distorted CsI12 cuboctahedra that share corners with six equivalent Cs(1)I12 cuboctahedra, corners with four equivalent Cr(1)I6 octahedra, faces with eight equivalent Cs(1)I12 cuboctahedra, and faces with four equivalent Cr(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 16-26°. Cr(1) is bonded to three equivalent I(1) and three equivalent I(2) atoms to form CrI6 octahedra that share corners with six equivalent Cs(1)I12 cuboctahedra, faces with six equivalent Cs(1)I12 cuboctahedra, and  a faceface with one Cr(1)I6 octahedra. There are two inequivalent I sites. In the first I site, I(2) is bonded in a distorted single-bond geometry to four equivalent Cs(1) and one Cr(1) atom. In the second I site, I(1) is bonded in a 2-coordinate geometry to four equivalent Cs(1) and two equivalent Cr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs3Cr2I9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.743
_cell_length_b   10.744
_cell_length_c   10.743
_cell_angle_alpha   81.241
_cell_angle_beta   81.244
_cell_angle_gamma   81.239
_symmetry_Int_Tables_number   1
_cell_volume   1200.521
_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
  Cs  Cs0  1  0.589  0.911  0.250  1.0
  Cs  Cs1  1  0.911  0.250  0.589  1.0
  Cs  Cs2  1  0.250  0.589  0.911  1.0
  Cs  Cs3  1  0.411  0.089  0.750  1.0
  Cs  Cs4  1  0.089  0.750  0.411  1.0
  Cs  Cs5  1  0.750  0.411  0.089  1.0
  Cr  Cr6  1  0.835  0.834  0.834  1.0
  Cr  Cr7  1  0.666  0.666  0.665  1.0
  Cr  Cr8  1  0.166  0.165  0.166  1.0
  Cr  Cr9  1  0.334  0.335  0.335  1.0
  I  I10  1  0.096  0.405  0.250  1.0
  I  I11  1  0.405  0.250  0.096  1.0
  I  I12  1  0.250  0.096  0.405  1.0
  I  I13  1  0.905  0.596  0.750  1.0
  I  I14  1  0.595  0.750  0.904  1.0
  I  I15  1  0.750  0.905  0.595  1.0
  I  I16  1  0.262  0.935  0.095  1.0
  I  I17  1  0.935  0.095  0.262  1.0
  I  I18  1  0.095  0.262  0.935  1.0
  I  I19  1  0.565  0.238  0.405  1.0
  I  I20  1  0.238  0.405  0.565  1.0
  I  I21  1  0.405  0.565  0.239  1.0
  I  I22  1  0.738  0.065  0.905  1.0
  I  I23  1  0.065  0.905  0.738  1.0
  I  I24  1  0.905  0.738  0.065  1.0
  I  I25  1  0.435  0.762  0.595  1.0
  I  I26  1  0.762  0.595  0.435  1.0
  I  I27  1  0.595  0.435  0.762  1.0
[/CIF]
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The compound described by Cs3Cr2I9 crystallizes in the trigonal R-3c space group. Cs(1) is bonded to four equivalent I(1) and eight equivalent I(2) atoms to form distorted CsI12 cuboctahedra that share corners with six equivalent Cs(1)I12 cuboctahedra, corners with four equivalent Cr(1)I6 octahedra, faces with eight equivalent Cs(1)I12 cuboctahedra, and faces with four equivalent Cr(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 16-26°. Cr(1) is bonded to three equivalent I(1) and three equivalent I(2) atoms to form CrI6 octahedra that share corners with six equivalent Cs(1)I12 cuboctahedra, faces with six equivalent Cs(1)I12 cuboctahedra, and  a faceface with one Cr(1)I6 octahedra. There are two inequivalent I sites. In the first I site, I(2) is bonded in a distorted single-bond geometry to four equivalent Cs(1) and one Cr(1) atom. In the second I site, I(1) is bonded in a 2-coordinate geometry to four equivalent Cs(1) and two equivalent Cr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs3Cr2I9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.743
_cell_length_b   10.744
_cell_length_c   10.743
_cell_angle_alpha   81.241
_cell_angle_beta   81.244
_cell_angle_gamma   81.239
_symmetry_Int_Tables_number   1
_cell_volume   1200.521
_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
  Cs  Cs0  1  0.589  0.911  0.250  1.0
  Cs  Cs1  1  0.911  0.250  0.589  1.0
  Cs  Cs2  1  0.250  0.589  0.911  1.0
  Cs  Cs3  1  0.411  0.089  0.750  1.0
  Cs  Cs4  1  0.089  0.750  0.411  1.0
  Cs  Cs5  1  0.750  0.411  0.089  1.0
  Cr  Cr6  1  0.835  0.834  0.834  1.0
  Cr  Cr7  1  0.666  0.666  0.665  1.0
  Cr  Cr8  1  0.166  0.165  0.166  1.0
  Cr  Cr9  1  0.334  0.335  0.335  1.0
  I  I10  1  0.096  0.405  0.250  1.0
  I  I11  1  0.405  0.250  0.096  1.0
  I  I12  1  0.250  0.096  0.405  1.0
  I  I13  1  0.905  0.596  0.750  1.0
  I  I14  1  0.595  0.750  0.904  1.0
  I  I15  1  0.750  0.905  0.595  1.0
  I  I16  1  0.262  0.935  0.095  1.0
  I  I17  1  0.935  0.095  0.262  1.0
  I  I18  1  0.095  0.262  0.935  1.0
  I  I19  1  0.565  0.238  0.405  1.0
  I  I20  1  0.238  0.405  0.565  1.0
  I  I21  1  0.405  0.565  0.239  1.0
  I  I22  1  0.738  0.065  0.905  1.0
  I  I23  1  0.065  0.905  0.738  1.0
  I  I24  1  0.905  0.738  0.065  1.0
  I  I25  1  0.435  0.762  0.595  1.0
  I  I26  1  0.762  0.595  0.435  1.0
  I  I27  1  0.595  0.435  0.762  1.0
[/CIF]
.