data_KZr4Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.0
_cell_length_b   6.0
_cell_length_c   6.0
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KZr4Nb
_chemical_formula_sum   'K1 Zr4 Nb1'
_cell_volume   152.88
_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  0.0  0.0  0.0  1.0
  Zr  Zr2  1  0.27  0.27  0.22  1.0
  Zr  Zr3  1  0.22  0.22  0.22  1.0
  Zr  Zr4  1  0.22  0.27  0.27  1.0
  Zr  Zr5  1  0.27  0.22  0.27  1.0
  Nb  Nb1  1  0.37  0.37  0.37  1.0

data_KZr4Nb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.0
_cell_length_b   6.0
_cell_length_c   14.7
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   KZr4Nb
_chemical_formula_sum   'K3 Zr12 Nb3'
_cell_volume   458.64
_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
  K  K0  3  0.0  0.0  0.0  1.0
  Zr  Zr1  9  0.03  0.02  0.75  1.0
  Zr  Zr2  3  0.0  0.0  0.78  1.0
  Nb  Nb3  3  0.0  0.0  0.63  1.0

K Zr Zr Zr Zr Nb
K Zr Zr Zr Zr Nb 0 2 o - o 0 2 - o o 0 2 o o - 0 2 o o o 0 3 o - o 0 3 - o o 0 3 o o - 0 3 o o o 0 1 - o o 0 1 o - o 0 1 o o - 0 1 o o o 0 5 - o o 0 5 o - o 0 5 o o - 0 4 - o o 0 4 o - o 0 4 o o - 0 4 o o o 1 4 o o o 1 3 o o o 1 2 o o o 1 5 o o o 2 4 o o o 2 3 o o o 3 4 o o o 3 5 o o o 4 5 o o o 
KZr4Nb crystallizes in the trigonal R3m space group. K(1) is bonded in a 4-coordinate geometry to one Zr(2) and three equivalent Nb(1) atoms. The K(1)-Zr(2) bond length is 3.23 Å. All K(1)-Nb(1) bond lengths are 3.50 Å. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 2-coordinate geometry to one Zr(2), two equivalent Zr(1), and one Nb(1) atom. The Zr(1)-Zr(2) bond length is 0.51 Å. Both Zr(1)-Zr(1) bond lengths are 0.29 Å. The Zr(1)-Nb(1) bond length is 1.68 Å. In the second Zr site, Zr(2) is bonded in a distorted rectangular see-saw-like geometry to one K(1) and three equivalent Zr(1) atoms. Nb(1) is bonded to three equivalent K(1) and three equivalent Zr(1) atoms to form distorted corner-sharing NbK3Zr3 pentagonal pyramids.