data_ZrNbCl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   4.92
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZrNbCl2
_chemical_formula_sum   'Zr1 Nb1 Cl2'
_cell_volume   84.44
_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
  Zr  Zr3  1  0.48  0.48  0.48  1.0
  Nb  Nb2  1  0.74  0.74  0.74  1.0
  Cl  Cl0  1  0.22  0.22  0.22  1.0
  Cl  Cl1  1  0.0  0.0  0.0  1.0

data_ZrNbCl2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   12.06
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ZrNbCl2
_chemical_formula_sum   'Zr3 Nb3 Cl6'
_cell_volume   253.32
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Zr  Zr0  3  0.0  0.0  0.52  1.0
  Nb  Nb1  3  0.0  0.0  0.26  1.0
  Cl  Cl2  3  0.0  0.0  0.0  1.0
  Cl  Cl3  3  0.0  0.0  0.78  1.0

Zr Nb Cl Cl
Zr Nb Cl Cl 0 2 o o o 0 2 o o + 0 2 o + o 0 2 + o o 0 3 o o + 0 3 o + o 0 3 o + + 0 3 + o o 0 3 + o + 0 3 + + o 0 1 - o o 0 1 o - o 0 1 o o - 0 1 o o o 1 2 o o + 1 2 o + o 1 2 o + + 1 2 + o o 1 2 + o + 1 2 + + o 1 3 o + + 1 3 + o + 1 3 + + o 1 3 + + + 2 3 o o o 2 3 o o + 2 3 + o o 2 3 o + o 
ZrNbCl2 crystallizes in the trigonal R3m space group. Zr(1) is bonded in a 11-coordinate geometry to four equivalent Nb(1), three equivalent Cl(2), and four equivalent Cl(1) atoms. There are three shorter (2.98 Å) and one longer (3.12 Å) Zr(1)-Nb(1) bond length. All Zr(1)-Cl(2) bond lengths are 3.36 Å. There are three shorter (2.98 Å) and one longer (3.12 Å) Zr(1)-Cl(1) bond length. Nb(1) is bonded in a 11-coordinate geometry to four equivalent Zr(1), three equivalent Cl(1), and four equivalent Cl(2) atoms. All Nb(1)-Cl(1) bond lengths are 3.36 Å. There are three shorter (2.98 Å) and one longer (3.12 Å) Nb(1)-Cl(2) bond length. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to four equivalent Zr(1) and three equivalent Nb(1) atoms to form distorted ClZr4Nb3 tetrahedra that share corners with six equivalent Cl(1)Zr4Nb3 tetrahedra, edges with six equivalent Cl(1)Zr4Nb3 tetrahedra, edges with nine equivalent Cl(2)Zr3Nb4 tetrahedra, and  a faceface with one Cl(2)Zr3Nb4 tetrahedra. In the second Cl site, Cl(2) is bonded to three equivalent Zr(1) and four equivalent Nb(1) atoms to form distorted ClZr3Nb4 tetrahedra that share corners with six equivalent Cl(2)Zr3Nb4 tetrahedra, edges with six equivalent Cl(2)Zr3Nb4 tetrahedra, edges with nine equivalent Cl(1)Zr4Nb3 tetrahedra, and  a faceface with one Cl(1)Zr4Nb3 tetrahedra.