The material structure described by Cs3As2Cl9 crystallizes in the trigonal P321 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to six equivalent Cl(1) and six equivalent Cl(2) atoms to form CsCl12 cuboctahedra that share corners with six equivalent Cs(1)Cl12 cuboctahedra, corners with six equivalent Cs(2)Cl12 cuboctahedra, faces with six equivalent Cs(2)Cl12 cuboctahedra, and faces with six equivalent As(1)Cl6 octahedra. In the second Cs site, Cs(2) is bonded to three equivalent Cl(1) and nine equivalent Cl(2) atoms to form CsCl12 cuboctahedra that share corners with three equivalent Cs(1)Cl12 cuboctahedra, corners with nine equivalent Cs(2)Cl12 cuboctahedra, faces with three equivalent Cs(1)Cl12 cuboctahedra, faces with three equivalent Cs(2)Cl12 cuboctahedra, and faces with five equivalent As(1)Cl6 octahedra. As(1) is bonded to three equivalent Cl(1) and three equivalent Cl(2) atoms to form AsCl6 octahedra that share corners with three equivalent As(1)Cl6 octahedra, faces with three equivalent Cs(1)Cl12 cuboctahedra, and faces with five equivalent Cs(2)Cl12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent As(1) atoms to form a mixture of distorted corner and face-sharing ClCs4As2 octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the second Cl site, Cl(2) is bonded in a distorted single-bond geometry to one Cs(1), three equivalent Cs(2), and one As(1) atom. is represented by the CIF file [CIF]
data_Cs3As2Cl9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.568
_cell_length_b   7.568
_cell_length_c   9.139
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   453.227
_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  0.000  0.000  0.000  1.0
  Cs  Cs1  1  0.667  0.333  0.680  1.0
  Cs  Cs2  1  0.333  0.667  0.320  1.0
  As  As3  1  0.667  0.333  0.183  1.0
  As  As4  1  0.333  0.667  0.817  1.0
  Cl  Cl5  1  0.484  0.000  0.000  1.0
  Cl  Cl6  1  0.516  0.516  0.000  1.0
  Cl  Cl7  1  0.000  0.484  0.000  1.0
  Cl  Cl8  1  0.173  0.805  0.676  1.0
  Cl  Cl9  1  0.632  0.827  0.676  1.0
  Cl  Cl10  1  0.195  0.368  0.676  1.0
  Cl  Cl11  1  0.827  0.632  0.324  1.0
  Cl  Cl12  1  0.805  0.173  0.324  1.0
  Cl  Cl13  1  0.368  0.195  0.324  1.0
[/CIF]
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The material structure described by Cs3As2Cl9 crystallizes in the trigonal P321 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to six equivalent Cl(1) and six equivalent Cl(2) atoms to form CsCl12 cuboctahedra that share corners with six equivalent Cs(1)Cl12 cuboctahedra, corners with six equivalent Cs(2)Cl12 cuboctahedra, faces with six equivalent Cs(2)Cl12 cuboctahedra, and faces with six equivalent As(1)Cl6 octahedra. In the second Cs site, Cs(2) is bonded to three equivalent Cl(1) and nine equivalent Cl(2) atoms to form CsCl12 cuboctahedra that share corners with three equivalent Cs(1)Cl12 cuboctahedra, corners with nine equivalent Cs(2)Cl12 cuboctahedra, faces with three equivalent Cs(1)Cl12 cuboctahedra, faces with three equivalent Cs(2)Cl12 cuboctahedra, and faces with five equivalent As(1)Cl6 octahedra. As(1) is bonded to three equivalent Cl(1) and three equivalent Cl(2) atoms to form AsCl6 octahedra that share corners with three equivalent As(1)Cl6 octahedra, faces with three equivalent Cs(1)Cl12 cuboctahedra, and faces with five equivalent Cs(2)Cl12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent As(1) atoms to form a mixture of distorted corner and face-sharing ClCs4As2 octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the second Cl site, Cl(2) is bonded in a distorted single-bond geometry to one Cs(1), three equivalent Cs(2), and one As(1) atom. is represented by the CIF file [CIF]
data_Cs3As2Cl9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.568
_cell_length_b   7.568
_cell_length_c   9.139
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   453.227
_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  0.000  0.000  0.000  1.0
  Cs  Cs1  1  0.667  0.333  0.680  1.0
  Cs  Cs2  1  0.333  0.667  0.320  1.0
  As  As3  1  0.667  0.333  0.183  1.0
  As  As4  1  0.333  0.667  0.817  1.0
  Cl  Cl5  1  0.484  0.000  0.000  1.0
  Cl  Cl6  1  0.516  0.516  0.000  1.0
  Cl  Cl7  1  0.000  0.484  0.000  1.0
  Cl  Cl8  1  0.173  0.805  0.676  1.0
  Cl  Cl9  1  0.632  0.827  0.676  1.0
  Cl  Cl10  1  0.195  0.368  0.676  1.0
  Cl  Cl11  1  0.827  0.632  0.324  1.0
  Cl  Cl12  1  0.805  0.173  0.324  1.0
  Cl  Cl13  1  0.368  0.195  0.324  1.0
[/CIF]
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