data_K2CuPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.54
_cell_length_b   6.54
_cell_length_c   6.54
_cell_angle_alpha   137.32
_cell_angle_beta   137.32
_cell_angle_gamma   61.94
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K2CuPb
_chemical_formula_sum   'K2 Cu1 Pb1'
_cell_volume   126.84
_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  0.38  0.0  0.8  1.0
  K  K2  1  0.0  0.38  0.8  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0
  Pb  Pb3  1  0.0  0.0  0.6  1.0

data_K2CuPb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.73
_cell_length_b   6.73
_cell_length_c   6.54
_cell_angle_alpha   90.0
_cell_angle_beta   120.97
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   K2CuPb
_chemical_formula_sum   'K4 Cu2 Pb2'
_cell_volume   253.69
_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  4  0.39  0.19  0.58  1.0
  Cu  Cu1  2  0.0  0.0  0.0  1.0
  Pb  Pb2  2  0.4  0.0  0.4  1.0

K K Cu Pb
K K Cu Pb 0 3 o o o 0 2 + o + 1 3 o o o 1 2 o + + 2 3 o o - 