The structure described by KLuNb6Cl18 crystallizes in the trigonal R3 space group. K(1) is bonded to three equivalent Cl(2), three equivalent Cl(3), three equivalent Cl(5), and three equivalent Cl(6) atoms to form KCl12 cuboctahedra that share corners with three equivalent Lu(1)Cl6 octahedra, corners with three equivalent Nb(1)Cl5 square pyramids, corners with three equivalent Nb(2)Cl5 square pyramids, edges with three equivalent Nb(1)Cl5 square pyramids, and faces with three equivalent Nb(2)Cl5 square pyramids. The corner-sharing octahedral tilt angles are 51°. Lu(1) is bonded to three equivalent Cl(3) and three equivalent Cl(4) atoms to form LuCl6 octahedra that share corners with three equivalent K(1)Cl12 cuboctahedra, corners with three equivalent Nb(1)Cl5 square pyramids, and corners with three equivalent Nb(2)Cl5 square pyramids. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one Cl(1), one Cl(2), one Cl(4), and two equivalent Cl(5) atoms to form distorted NbCl5 square pyramids that share  a cornercorner with one K(1)Cl12 cuboctahedra,  a cornercorner with one Lu(1)Cl6 octahedra, corners with two equivalent Nb(1)Cl5 square pyramids, corners with two equivalent Nb(2)Cl5 square pyramids, and  an edgeedge with one K(1)Cl12 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. In the second Nb site, Nb(2) is bonded to one Cl(1), one Cl(2), one Cl(3), and two equivalent Cl(6) atoms to form distorted NbCl5 square pyramids that share  a cornercorner with one K(1)Cl12 cuboctahedra,  a cornercorner with one Lu(1)Cl6 octahedra, corners with two equivalent Nb(1)Cl5 square pyramids, corners with two equivalent Nb(2)Cl5 square pyramids, and  a faceface with one K(1)Cl12 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent Cl sites. In the first Cl site, Cl(4) is bonded in a distorted bent 150 degrees geometry to one Lu(1) and one Nb(1) atom. In the second Cl site, Cl(5) is bonded in a 3-coordinate geometry to one K(1) and two equivalent Nb(1) atoms. In the third Cl site, Cl(6) is bonded in a 2-coordinate geometry to one K(1) and two equivalent Nb(2) atoms. In the fourth Cl site, Cl(1) is bonded in a 2-coordinate geometry to one Nb(1) and one Nb(2) atom. In the fifth Cl site, Cl(2) is bonded in a 3-coordinate geometry to one K(1), one Nb(1), and one Nb(2) atom. In the sixth Cl site, Cl(3) is bonded in a 3-coordinate geometry to one K(1), one Lu(1), and one Nb(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KLu(NbCl3)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.119
_cell_length_b   10.119
_cell_length_c   10.119
_cell_angle_alpha   55.203
_cell_angle_beta   55.203
_cell_angle_gamma   55.203
_symmetry_Int_Tables_number   1
_cell_volume   650.918
_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
  K  K0  1  0.722  0.722  0.722  1.0
  Lu  Lu1  1  0.998  0.998  0.998  1.0
  Nb  Nb2  1  0.349  0.588  0.703  1.0
  Nb  Nb3  1  0.588  0.703  0.349  1.0
  Nb  Nb4  1  0.703  0.349  0.588  1.0
  Nb  Nb5  1  0.652  0.411  0.298  1.0
  Nb  Nb6  1  0.411  0.298  0.652  1.0
  Nb  Nb7  1  0.298  0.652  0.411  1.0
  Cl  Cl8  1  0.222  0.363  0.918  1.0
  Cl  Cl9  1  0.363  0.918  0.222  1.0
  Cl  Cl10  1  0.918  0.222  0.363  1.0
  Cl  Cl11  1  0.778  0.637  0.081  1.0
  Cl  Cl12  1  0.637  0.081  0.778  1.0
  Cl  Cl13  1  0.081  0.778  0.637  1.0
  Cl  Cl14  1  0.847  0.302  0.028  1.0
  Cl  Cl15  1  0.302  0.028  0.847  1.0
  Cl  Cl16  1  0.028  0.847  0.302  1.0
  Cl  Cl17  1  0.154  0.700  0.971  1.0
  Cl  Cl18  1  0.700  0.971  0.154  1.0
  Cl  Cl19  1  0.971  0.154  0.700  1.0
  Cl  Cl20  1  0.561  0.426  0.843  1.0
  Cl  Cl21  1  0.426  0.843  0.561  1.0
  Cl  Cl22  1  0.843  0.561  0.426  1.0
  Cl  Cl23  1  0.440  0.573  0.157  1.0
  Cl  Cl24  1  0.573  0.157  0.440  1.0
  Cl  Cl25  1  0.157  0.440  0.573  1.0
[/CIF]
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The structure described by KLuNb6Cl18 crystallizes in the trigonal R3 space group. K(1) is bonded to three equivalent Cl(2), three equivalent Cl(3), three equivalent Cl(5), and three equivalent Cl(6) atoms to form KCl12 cuboctahedra that share corners with three equivalent Lu(1)Cl6 octahedra, corners with three equivalent Nb(1)Cl5 square pyramids, corners with three equivalent Nb(2)Cl5 square pyramids, edges with three equivalent Nb(1)Cl5 square pyramids, and faces with three equivalent Nb(2)Cl5 square pyramids. The corner-sharing octahedral tilt angles are 51°. Lu(1) is bonded to three equivalent Cl(3) and three equivalent Cl(4) atoms to form LuCl6 octahedra that share corners with three equivalent K(1)Cl12 cuboctahedra, corners with three equivalent Nb(1)Cl5 square pyramids, and corners with three equivalent Nb(2)Cl5 square pyramids. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one Cl(1), one Cl(2), one Cl(4), and two equivalent Cl(5) atoms to form distorted NbCl5 square pyramids that share  a cornercorner with one K(1)Cl12 cuboctahedra,  a cornercorner with one Lu(1)Cl6 octahedra, corners with two equivalent Nb(1)Cl5 square pyramids, corners with two equivalent Nb(2)Cl5 square pyramids, and  an edgeedge with one K(1)Cl12 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. In the second Nb site, Nb(2) is bonded to one Cl(1), one Cl(2), one Cl(3), and two equivalent Cl(6) atoms to form distorted NbCl5 square pyramids that share  a cornercorner with one K(1)Cl12 cuboctahedra,  a cornercorner with one Lu(1)Cl6 octahedra, corners with two equivalent Nb(1)Cl5 square pyramids, corners with two equivalent Nb(2)Cl5 square pyramids, and  a faceface with one K(1)Cl12 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent Cl sites. In the first Cl site, Cl(4) is bonded in a distorted bent 150 degrees geometry to one Lu(1) and one Nb(1) atom. In the second Cl site, Cl(5) is bonded in a 3-coordinate geometry to one K(1) and two equivalent Nb(1) atoms. In the third Cl site, Cl(6) is bonded in a 2-coordinate geometry to one K(1) and two equivalent Nb(2) atoms. In the fourth Cl site, Cl(1) is bonded in a 2-coordinate geometry to one Nb(1) and one Nb(2) atom. In the fifth Cl site, Cl(2) is bonded in a 3-coordinate geometry to one K(1), one Nb(1), and one Nb(2) atom. In the sixth Cl site, Cl(3) is bonded in a 3-coordinate geometry to one K(1), one Lu(1), and one Nb(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KLu(NbCl3)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.119
_cell_length_b   10.119
_cell_length_c   10.119
_cell_angle_alpha   55.203
_cell_angle_beta   55.203
_cell_angle_gamma   55.203
_symmetry_Int_Tables_number   1
_cell_volume   650.918
_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
  K  K0  1  0.722  0.722  0.722  1.0
  Lu  Lu1  1  0.998  0.998  0.998  1.0
  Nb  Nb2  1  0.349  0.588  0.703  1.0
  Nb  Nb3  1  0.588  0.703  0.349  1.0
  Nb  Nb4  1  0.703  0.349  0.588  1.0
  Nb  Nb5  1  0.652  0.411  0.298  1.0
  Nb  Nb6  1  0.411  0.298  0.652  1.0
  Nb  Nb7  1  0.298  0.652  0.411  1.0
  Cl  Cl8  1  0.222  0.363  0.918  1.0
  Cl  Cl9  1  0.363  0.918  0.222  1.0
  Cl  Cl10  1  0.918  0.222  0.363  1.0
  Cl  Cl11  1  0.778  0.637  0.081  1.0
  Cl  Cl12  1  0.637  0.081  0.778  1.0
  Cl  Cl13  1  0.081  0.778  0.637  1.0
  Cl  Cl14  1  0.847  0.302  0.028  1.0
  Cl  Cl15  1  0.302  0.028  0.847  1.0
  Cl  Cl16  1  0.028  0.847  0.302  1.0
  Cl  Cl17  1  0.154  0.700  0.971  1.0
  Cl  Cl18  1  0.700  0.971  0.154  1.0
  Cl  Cl19  1  0.971  0.154  0.700  1.0
  Cl  Cl20  1  0.561  0.426  0.843  1.0
  Cl  Cl21  1  0.426  0.843  0.561  1.0
  Cl  Cl22  1  0.843  0.561  0.426  1.0
  Cl  Cl23  1  0.440  0.573  0.157  1.0
  Cl  Cl24  1  0.573  0.157  0.440  1.0
  Cl  Cl25  1  0.157  0.440  0.573  1.0
[/CIF]
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