data_K2NbPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.98
_cell_length_b   12.98
_cell_length_c   12.98
_cell_angle_alpha   14.67
_cell_angle_beta   14.67
_cell_angle_gamma   14.67
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K2NbPb
_chemical_formula_sum   'K2 Nb1 Pb1'
_cell_volume   121.98
_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  0.88  1.0
  K  K1  1  0.0  0.0  0.63  1.0
  Nb  Nb2  1  0.0  0.0  0.0  1.0
  Pb  Pb3  1  0.0  0.0  0.25  1.0

data_K2NbPb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.74
_cell_length_b   3.31
_cell_length_c   12.98
_cell_angle_alpha   90.0
_cell_angle_beta   98.48
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   K2NbPb
_chemical_formula_sum   'K4 Nb2 Pb2'
_cell_volume   243.96
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  -0.0  0.0  0.37  1.0
  K  K1  2  -0.0  0.0  0.12  1.0
  Nb  Nb2  2  0.0  0.0  0.0  1.0
  Pb  Pb3  2  -0.0  0.0  0.75  1.0

K K Nb Pb