The material described by Cs3Bi2Br9 crystallizes in the trigonal P-3m1 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 nine equivalent Cs(1)Br12 cuboctahedra, faces with three equivalent Cs(1)Br12 cuboctahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, and faces with five equivalent Bi(1)Br6 octahedra. 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 Bi(1)Br6 octahedra. Bi(1) is bonded to three equivalent Br(1) and three equivalent Br(2) atoms to form BiBr6 octahedra that share corners with three equivalent Bi(1)Br6 octahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, and faces with five equivalent Cs(1)Br12 cuboctahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded to one Cs(2), three equivalent Cs(1), and one Bi(1) atom to form distorted BrCs4Bi square pyramids that share corners with eight equivalent Br(2)Cs4Bi2 octahedra, corners with thirteen equivalent Br(1)Cs4Bi square pyramids, edges with two equivalent Br(2)Cs4Bi2 octahedra, edges with six equivalent Br(1)Cs4Bi square pyramids, faces with two equivalent Br(2)Cs4Bi2 octahedra, and faces with two equivalent Br(1)Cs4Bi square pyramids. The corner-sharing octahedral tilt angles range from 1-61°. In the second Br site, Br(2) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Bi(1) atoms to form BrCs4Bi2 octahedra that share corners with six equivalent Br(2)Cs4Bi2 octahedra, corners with sixteen equivalent Br(1)Cs4Bi square pyramids, edges with four equivalent Br(1)Cs4Bi square pyramids, faces with four equivalent Br(2)Cs4Bi2 octahedra, and faces with four equivalent Br(1)Cs4Bi square pyramids. The corner-sharing octahedral tilt angles range from 0-60°. is represented by the CIF file [CIF]
data_Cs3Bi2Br9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.014
_cell_length_b   8.014
_cell_length_c   9.945
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   553.131
_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
  Cs  Cs0  1  0.333  0.667  0.337  1.0
  Cs  Cs1  1  0.667  0.333  0.663  1.0
  Cs  Cs2  1  0.000  0.000  0.000  1.0
  Bi  Bi3  1  0.333  0.667  0.810  1.0
  Bi  Bi4  1  0.667  0.333  0.190  1.0
  Br  Br5  1  0.167  0.334  0.662  1.0
  Br  Br6  1  0.666  0.833  0.662  1.0
  Br  Br7  1  0.167  0.833  0.662  1.0
  Br  Br8  1  0.833  0.666  0.338  1.0
  Br  Br9  1  0.833  0.167  0.338  1.0
  Br  Br10  1  0.500  0.500  0.000  1.0
  Br  Br11  1  0.500  0.000  0.000  1.0
  Br  Br12  1  0.000  0.500  0.000  1.0
  Br  Br13  1  0.334  0.167  0.338  1.0
[/CIF]
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The material described by Cs3Bi2Br9 crystallizes in the trigonal P-3m1 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 nine equivalent Cs(1)Br12 cuboctahedra, faces with three equivalent Cs(1)Br12 cuboctahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, and faces with five equivalent Bi(1)Br6 octahedra. 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 Bi(1)Br6 octahedra. Bi(1) is bonded to three equivalent Br(1) and three equivalent Br(2) atoms to form BiBr6 octahedra that share corners with three equivalent Bi(1)Br6 octahedra, faces with three equivalent Cs(2)Br12 cuboctahedra, and faces with five equivalent Cs(1)Br12 cuboctahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded to one Cs(2), three equivalent Cs(1), and one Bi(1) atom to form distorted BrCs4Bi square pyramids that share corners with eight equivalent Br(2)Cs4Bi2 octahedra, corners with thirteen equivalent Br(1)Cs4Bi square pyramids, edges with two equivalent Br(2)Cs4Bi2 octahedra, edges with six equivalent Br(1)Cs4Bi square pyramids, faces with two equivalent Br(2)Cs4Bi2 octahedra, and faces with two equivalent Br(1)Cs4Bi square pyramids. The corner-sharing octahedral tilt angles range from 1-61°. In the second Br site, Br(2) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Bi(1) atoms to form BrCs4Bi2 octahedra that share corners with six equivalent Br(2)Cs4Bi2 octahedra, corners with sixteen equivalent Br(1)Cs4Bi square pyramids, edges with four equivalent Br(1)Cs4Bi square pyramids, faces with four equivalent Br(2)Cs4Bi2 octahedra, and faces with four equivalent Br(1)Cs4Bi square pyramids. The corner-sharing octahedral tilt angles range from 0-60°. is represented by the CIF file [CIF]
data_Cs3Bi2Br9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.014
_cell_length_b   8.014
_cell_length_c   9.945
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   553.131
_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
  Cs  Cs0  1  0.333  0.667  0.337  1.0
  Cs  Cs1  1  0.667  0.333  0.663  1.0
  Cs  Cs2  1  0.000  0.000  0.000  1.0
  Bi  Bi3  1  0.333  0.667  0.810  1.0
  Bi  Bi4  1  0.667  0.333  0.190  1.0
  Br  Br5  1  0.167  0.334  0.662  1.0
  Br  Br6  1  0.666  0.833  0.662  1.0
  Br  Br7  1  0.167  0.833  0.662  1.0
  Br  Br8  1  0.833  0.666  0.338  1.0
  Br  Br9  1  0.833  0.167  0.338  1.0
  Br  Br10  1  0.500  0.500  0.000  1.0
  Br  Br11  1  0.500  0.000  0.000  1.0
  Br  Br12  1  0.000  0.500  0.000  1.0
  Br  Br13  1  0.334  0.167  0.338  1.0
[/CIF]
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