The compound described by Cu4IBr3 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to three equivalent Br(1) and three equivalent Br(2) atoms to form CuBr6 octahedra that share corners with three equivalent Cu(1)Br6 octahedra, corners with three equivalent Cu(2)I3Br3 octahedra, edges with three equivalent Cu(2)I3Br3 octahedra, and edges with nine equivalent Cu(1)Br6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Cu site, Cu(2) is bonded to three equivalent I(1) and three equivalent Br(1) atoms to form CuI3Br3 octahedra that share corners with three equivalent Cu(1)Br6 octahedra, corners with three equivalent Cu(2)I3Br3 octahedra, edges with three equivalent Cu(1)Br6 octahedra, and edges with nine equivalent Cu(2)I3Br3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. I(1) is bonded to six equivalent Cu(2) atoms to form ICu6 octahedra that share corners with six equivalent Br(1)Cu6 octahedra, edges with six equivalent I(1)Cu6 octahedra, and edges with six equivalent Br(1)Cu6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded to three equivalent Cu(1) and three equivalent Cu(2) atoms to form BrCu6 octahedra that share corners with three equivalent I(1)Cu6 octahedra, corners with three equivalent Br(2)Cu6 octahedra, edges with three equivalent I(1)Cu6 octahedra, edges with three equivalent Br(2)Cu6 octahedra, and edges with six equivalent Br(1)Cu6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Br site, Br(2) is bonded to six equivalent Cu(1) atoms to form a mixture of corner and edge-sharing BrCu6 octahedra. The corner-sharing octahedral tilt angles are 1°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cu4IBr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.761
_cell_length_b   12.761
_cell_length_c   12.761
_cell_angle_alpha   17.492
_cell_angle_beta   17.492
_cell_angle_gamma   17.492
_symmetry_Int_Tables_number   1
_cell_volume   163.830
_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
  Cu  Cu0  1  0.625  0.625  0.625  1.0
  Cu  Cu1  1  0.375  0.375  0.375  1.0
  Cu  Cu2  1  0.876  0.876  0.876  1.0
  Cu  Cu3  1  0.124  0.124  0.124  1.0
  I  I4  1  0.500  0.500  0.500  1.0
  Br  Br5  1  0.748  0.748  0.748  1.0
  Br  Br6  1  0.000  0.000  0.000  1.0
  Br  Br7  1  0.252  0.252  0.252  1.0
[/CIF]
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The compound described by Cu4IBr3 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to three equivalent Br(1) and three equivalent Br(2) atoms to form CuBr6 octahedra that share corners with three equivalent Cu(1)Br6 octahedra, corners with three equivalent Cu(2)I3Br3 octahedra, edges with three equivalent Cu(2)I3Br3 octahedra, and edges with nine equivalent Cu(1)Br6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Cu site, Cu(2) is bonded to three equivalent I(1) and three equivalent Br(1) atoms to form CuI3Br3 octahedra that share corners with three equivalent Cu(1)Br6 octahedra, corners with three equivalent Cu(2)I3Br3 octahedra, edges with three equivalent Cu(1)Br6 octahedra, and edges with nine equivalent Cu(2)I3Br3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. I(1) is bonded to six equivalent Cu(2) atoms to form ICu6 octahedra that share corners with six equivalent Br(1)Cu6 octahedra, edges with six equivalent I(1)Cu6 octahedra, and edges with six equivalent Br(1)Cu6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded to three equivalent Cu(1) and three equivalent Cu(2) atoms to form BrCu6 octahedra that share corners with three equivalent I(1)Cu6 octahedra, corners with three equivalent Br(2)Cu6 octahedra, edges with three equivalent I(1)Cu6 octahedra, edges with three equivalent Br(2)Cu6 octahedra, and edges with six equivalent Br(1)Cu6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Br site, Br(2) is bonded to six equivalent Cu(1) atoms to form a mixture of corner and edge-sharing BrCu6 octahedra. The corner-sharing octahedral tilt angles are 1°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cu4IBr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.761
_cell_length_b   12.761
_cell_length_c   12.761
_cell_angle_alpha   17.492
_cell_angle_beta   17.492
_cell_angle_gamma   17.492
_symmetry_Int_Tables_number   1
_cell_volume   163.830
_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
  Cu  Cu0  1  0.625  0.625  0.625  1.0
  Cu  Cu1  1  0.375  0.375  0.375  1.0
  Cu  Cu2  1  0.876  0.876  0.876  1.0
  Cu  Cu3  1  0.124  0.124  0.124  1.0
  I  I4  1  0.500  0.500  0.500  1.0
  Br  Br5  1  0.748  0.748  0.748  1.0
  Br  Br6  1  0.000  0.000  0.000  1.0
  Br  Br7  1  0.252  0.252  0.252  1.0
[/CIF]
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