data_K2NbBr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.21
_cell_length_b   7.21
_cell_length_c   7.21
_cell_angle_alpha   140.33
_cell_angle_beta   140.33
_cell_angle_gamma   57.36
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K2NbBr
_chemical_formula_sum   'K2 Nb1 Br1'
_cell_volume   151.36
_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  K1  1  0.0  0.45  0.16  1.0
  K  K2  1  0.0  0.0  0.0  1.0
  Nb  Nb3  1  0.45  0.0  0.16  1.0
  Br  Br0  1  0.0  0.0  0.32  1.0

data_K2NbBr
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.89
_cell_length_b   4.89
_cell_length_c   7.21
_cell_angle_alpha   109.84
_cell_angle_beta   109.84
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K2NbBr
_chemical_formula_sum   'K2 Nb1 Br1'
_cell_volume   151.36
_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
  K  K1  1  0.28  0.45  0.28  1.0
  Nb  Nb2  1  0.84  0.0  0.28  1.0
  Br  Br3  1  0.68  0.0  0.68  1.0

K K Nb Br
K2NbBr crystallizes in the triclinic P1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 1-coordinate geometry to four equivalent Nb(1) and one Br(1) atom. There are a spread of K(1)-Nb(1) bond distances ranging from 3.09-3.83 Å. The K(1)-Br(1) bond length is 3.18 Å. In the second K site, K(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Nb(1) and one Br(1) atom. There is one shorter (2.43 Å) and one longer (3.91 Å) K(2)-Nb(1) bond length. The K(2)-Br(1) bond length is 2.34 Å. Nb(1) is bonded in a 7-coordinate geometry to two equivalent K(2), four equivalent K(1), and one Br(1) atom. The Nb(1)-Br(1) bond length is 3.18 Å. Br(1) is bonded in a 3-coordinate geometry to one K(1), one K(2), and one Nb(1) atom.