The material described by Cs3Cr2Br9 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to three equivalent Br(2) and nine equivalent Br(1) atoms to form CsBr12 cuboctahedra that share corners with three equivalent Cs(2)Br12 cuboctahedra, corners with six equivalent Cs(1)Br12 cuboctahedra, corners with three equivalent Cr(1)Br6 octahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, faces with four equivalent Cs(1)Br12 cuboctahedra, and faces with four equivalent Cr(1)Br6 octahedra. The corner-sharing octahedral tilt angles are 14°. In the second Cs site, Cs(2) is bonded to six equivalent Br(1) and six equivalent Br(2) atoms to form CsBr12 cuboctahedra that share corners with six equivalent Cs(1)Br12 cuboctahedra, corners with six equivalent Cs(2)Br12 cuboctahedra, faces with six equivalent Cs(1)Br12 cuboctahedra, and faces with six equivalent Cr(1)Br6 octahedra. Cr(1) is bonded to three equivalent Br(1) and three equivalent Br(2) atoms to form CrBr6 octahedra that share corners with three equivalent Cs(1)Br12 cuboctahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, faces with four equivalent Cs(1)Br12 cuboctahedra, and  a faceface with one Cr(1)Br6 octahedra. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted single-bond geometry to one Cs(2), three equivalent Cs(1), and one Cr(1) atom. In the second Br site, Br(2) is bonded in a 2-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Cr(1) atoms. is represented by the CIF file [CIF]
data_Cs3Cr2Br9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.623
_cell_length_b   7.623
_cell_length_c   19.098
_cell_angle_alpha   90.003
_cell_angle_beta   89.998
_cell_angle_gamma   119.999
_symmetry_Int_Tables_number   1
_cell_volume   961.193
_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  0.667  0.333  0.927  1.0
  Cs  Cs1  1  0.333  0.667  0.427  1.0
  Cs  Cs2  1  0.667  0.333  0.572  1.0
  Cs  Cs3  1  0.333  0.667  0.072  1.0
  Cs  Cs4  1  1.000  1.000  0.750  1.0
  Cs  Cs5  1  1.000  1.000  0.250  1.0
  Cr  Cr6  1  0.333  0.667  0.662  1.0
  Cr  Cr7  1  0.667  0.333  0.162  1.0
  Cr  Cr8  1  0.667  0.333  0.338  1.0
  Cr  Cr9  1  0.333  0.667  0.838  1.0
  Br  Br10  1  0.823  0.646  0.407  1.0
  Br  Br11  1  0.177  0.354  0.907  1.0
  Br  Br12  1  0.177  0.823  0.907  1.0
  Br  Br13  1  0.177  0.354  0.593  1.0
  Br  Br14  1  0.646  0.823  0.907  1.0
  Br  Br15  1  0.354  0.177  0.407  1.0
  Br  Br16  1  0.032  0.516  0.750  1.0
  Br  Br17  1  0.823  0.177  0.407  1.0
  Br  Br18  1  0.516  0.032  0.250  1.0
  Br  Br19  1  0.484  0.516  0.750  1.0
  Br  Br20  1  0.516  0.484  0.250  1.0
  Br  Br21  1  0.968  0.484  0.250  1.0
  Br  Br22  1  0.354  0.177  0.093  1.0
  Br  Br23  1  0.484  0.968  0.750  1.0
  Br  Br24  1  0.823  0.646  0.093  1.0
  Br  Br25  1  0.177  0.823  0.593  1.0
  Br  Br26  1  0.646  0.823  0.593  1.0
  Br  Br27  1  0.823  0.177  0.093  1.0
[/CIF]
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The material described by Cs3Cr2Br9 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to three equivalent Br(2) and nine equivalent Br(1) atoms to form CsBr12 cuboctahedra that share corners with three equivalent Cs(2)Br12 cuboctahedra, corners with six equivalent Cs(1)Br12 cuboctahedra, corners with three equivalent Cr(1)Br6 octahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, faces with four equivalent Cs(1)Br12 cuboctahedra, and faces with four equivalent Cr(1)Br6 octahedra. The corner-sharing octahedral tilt angles are 14°. In the second Cs site, Cs(2) is bonded to six equivalent Br(1) and six equivalent Br(2) atoms to form CsBr12 cuboctahedra that share corners with six equivalent Cs(1)Br12 cuboctahedra, corners with six equivalent Cs(2)Br12 cuboctahedra, faces with six equivalent Cs(1)Br12 cuboctahedra, and faces with six equivalent Cr(1)Br6 octahedra. Cr(1) is bonded to three equivalent Br(1) and three equivalent Br(2) atoms to form CrBr6 octahedra that share corners with three equivalent Cs(1)Br12 cuboctahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, faces with four equivalent Cs(1)Br12 cuboctahedra, and  a faceface with one Cr(1)Br6 octahedra. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted single-bond geometry to one Cs(2), three equivalent Cs(1), and one Cr(1) atom. In the second Br site, Br(2) is bonded in a 2-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Cr(1) atoms. is represented by the CIF file [CIF]
data_Cs3Cr2Br9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.623
_cell_length_b   7.623
_cell_length_c   19.098
_cell_angle_alpha   90.003
_cell_angle_beta   89.998
_cell_angle_gamma   119.999
_symmetry_Int_Tables_number   1
_cell_volume   961.193
_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  0.667  0.333  0.927  1.0
  Cs  Cs1  1  0.333  0.667  0.427  1.0
  Cs  Cs2  1  0.667  0.333  0.572  1.0
  Cs  Cs3  1  0.333  0.667  0.072  1.0
  Cs  Cs4  1  1.000  1.000  0.750  1.0
  Cs  Cs5  1  1.000  1.000  0.250  1.0
  Cr  Cr6  1  0.333  0.667  0.662  1.0
  Cr  Cr7  1  0.667  0.333  0.162  1.0
  Cr  Cr8  1  0.667  0.333  0.338  1.0
  Cr  Cr9  1  0.333  0.667  0.838  1.0
  Br  Br10  1  0.823  0.646  0.407  1.0
  Br  Br11  1  0.177  0.354  0.907  1.0
  Br  Br12  1  0.177  0.823  0.907  1.0
  Br  Br13  1  0.177  0.354  0.593  1.0
  Br  Br14  1  0.646  0.823  0.907  1.0
  Br  Br15  1  0.354  0.177  0.407  1.0
  Br  Br16  1  0.032  0.516  0.750  1.0
  Br  Br17  1  0.823  0.177  0.407  1.0
  Br  Br18  1  0.516  0.032  0.250  1.0
  Br  Br19  1  0.484  0.516  0.750  1.0
  Br  Br20  1  0.516  0.484  0.250  1.0
  Br  Br21  1  0.968  0.484  0.250  1.0
  Br  Br22  1  0.354  0.177  0.093  1.0
  Br  Br23  1  0.484  0.968  0.750  1.0
  Br  Br24  1  0.823  0.646  0.093  1.0
  Br  Br25  1  0.177  0.823  0.593  1.0
  Br  Br26  1  0.646  0.823  0.593  1.0
  Br  Br27  1  0.823  0.177  0.093  1.0
[/CIF]
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