The crystal structure described by K4Pb9 is Magnesium tetraboride-like structured and crystallizes in the monoclinic P2_1/m space group. There are five inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one Pb(1), one Pb(10), one Pb(11), one Pb(3), one Pb(4), one Pb(6), one Pb(8), and one Pb(9) atom. In the second K site, K(2) is bonded in a 7-coordinate geometry to one Pb(2), two equivalent Pb(10), two equivalent Pb(6), and two equivalent Pb(9) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to one Pb(1), one Pb(10), one Pb(2), one Pb(3), one Pb(6), one Pb(7), one Pb(8), and one Pb(9) atom. In the fourth K site, K(4) is bonded in a 8-coordinate geometry to one Pb(11), one Pb(12), one Pb(5), one Pb(6), one Pb(7), one Pb(8), and two equivalent Pb(4) atoms. In the fifth K site, K(5) is bonded in a 7-coordinate geometry to one Pb(12), one Pb(5), one Pb(7), two equivalent Pb(4), and two equivalent Pb(9) atoms. There are twelve inequivalent Pb sites. In the first Pb site, Pb(11) is bonded in a distorted body-centered cubic geometry to two equivalent K(1), two equivalent K(4), two equivalent Pb(4), and two equivalent Pb(6) atoms. In the second Pb site, Pb(12) is bonded in a 8-coordinate geometry to one K(5), two equivalent K(4), one Pb(1), two equivalent Pb(4), and two equivalent Pb(8) atoms. In the third Pb site, Pb(1) is bonded in a 9-coordinate geometry to two equivalent K(1), two equivalent K(3), one Pb(12), two equivalent Pb(6), and two equivalent Pb(8) atoms. In the fourth Pb site, Pb(2) is bonded in a 8-coordinate geometry to one K(2), two equivalent K(3), one Pb(7), two equivalent Pb(10), and two equivalent Pb(3) atoms. In the fifth Pb site, Pb(3) is bonded in a 1-coordinate geometry to one K(1), one K(3), one Pb(10), one Pb(2), one Pb(7), and one Pb(9) atom. In the sixth Pb site, Pb(4) is bonded in a 8-coordinate geometry to one K(1), one K(5), two equivalent K(4), one Pb(11), one Pb(12), one Pb(4), and one Pb(8) atom. In the seventh Pb site, Pb(5) is bonded in a 6-coordinate geometry to one K(5), two equivalent K(4), one Pb(7), and two equivalent Pb(9) atoms. In the eighth Pb site, Pb(6) is bonded in a 8-coordinate geometry to one K(1), one K(2), one K(3), one K(4), one Pb(1), one Pb(11), one Pb(6), and one Pb(8) atom. In the ninth Pb site, Pb(7) is bonded in a 9-coordinate geometry to one K(5), two equivalent K(3), two equivalent K(4), one Pb(2), one Pb(5), and two equivalent Pb(3) atoms. In the tenth Pb site, Pb(8) is bonded in a 7-coordinate geometry to one K(1), one K(3), one K(4), one Pb(1), one Pb(12), one Pb(4), and one Pb(6) atom. In the eleventh Pb site, Pb(9) is bonded in a 8-coordinate geometry to one K(1), one K(2), one K(3), one K(5), one Pb(10), one Pb(3), one Pb(5), and one Pb(9) atom. In the twelfth Pb site, Pb(10) is bonded in a 7-coordinate geometry to one K(1), one K(2), one K(3), one Pb(10), one Pb(2), one Pb(3), and one Pb(9) atom. is represented by the CIF card [CIF]
data_K4Pb9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.469
_cell_length_b   9.825
_cell_length_c   16.201
_cell_angle_alpha   76.806
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   2087.328
_cell_formula_units_Z   4
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  0.927  0.381  0.787  1.0
  K  K1  1  0.750  0.739  0.568  1.0
  K  K2  1  0.573  0.381  0.787  1.0
  K  K3  1  0.250  0.261  0.432  1.0
  K  K4  1  0.003  0.052  0.630  1.0
  K  K5  1  0.997  0.948  0.370  1.0
  K  K6  1  0.402  0.675  0.909  1.0
  K  K7  1  0.098  0.675  0.909  1.0
  K  K8  1  0.497  0.052  0.630  1.0
  K  K9  1  0.503  0.948  0.370  1.0
  K  K10  1  0.902  0.325  0.091  1.0
  K  K11  1  0.073  0.619  0.213  1.0
  K  K12  1  0.427  0.619  0.213  1.0
  K  K13  1  0.750  0.886  0.203  1.0
  K  K14  1  0.598  0.325  0.091  1.0
  K  K15  1  0.250  0.114  0.797  1.0
  Pb  Pb16  1  0.750  0.067  0.754  1.0
  Pb  Pb17  1  0.750  0.131  0.506  1.0
  Pb  Pb18  1  0.250  0.869  0.494  1.0
  Pb  Pb19  1  0.562  0.308  0.377  1.0
  Pb  Pb20  1  0.868  0.754  0.029  1.0
  Pb  Pb21  1  0.750  0.497  0.239  1.0
  Pb  Pb22  1  0.438  0.692  0.623  1.0
  Pb  Pb23  1  0.633  0.766  0.782  1.0
  Pb  Pb24  1  0.132  0.246  0.971  1.0
  Pb  Pb25  1  0.750  0.171  0.307  1.0
  Pb  Pb26  1  0.443  0.000  0.122  1.0
  Pb  Pb27  1  0.133  0.234  0.218  1.0
  Pb  Pb28  1  0.632  0.754  0.029  1.0
  Pb  Pb29  1  0.367  0.234  0.218  1.0
  Pb  Pb30  1  0.370  0.384  0.622  1.0
  Pb  Pb31  1  0.369  0.612  0.449  1.0
  Pb  Pb32  1  0.130  0.384  0.622  1.0
  Pb  Pb33  1  0.250  0.440  0.072  1.0
  Pb  Pb34  1  0.867  0.766  0.782  1.0
  Pb  Pb35  1  0.250  0.503  0.761  1.0
  Pb  Pb36  1  0.250  0.935  0.029  1.0
  Pb  Pb37  1  0.938  0.308  0.377  1.0
  Pb  Pb38  1  0.131  0.612  0.449  1.0
  Pb  Pb39  1  0.630  0.616  0.378  1.0
  Pb  Pb40  1  0.750  0.560  0.928  1.0
  Pb  Pb41  1  0.062  0.692  0.623  1.0
  Pb  Pb42  1  0.631  0.388  0.551  1.0
  Pb  Pb43  1  0.250  0.933  0.246  1.0
  Pb  Pb44  1  0.869  0.388  0.551  1.0
  Pb  Pb45  1  0.870  0.616  0.378  1.0
  Pb  Pb46  1  0.368  0.246  0.971  1.0
  Pb  Pb47  1  0.750  0.065  0.971  1.0
  Pb  Pb48  1  0.057  0.000  0.122  1.0
  Pb  Pb49  1  0.943  1.000  0.878  1.0
  Pb  Pb50  1  0.557  1.000  0.878  1.0
  Pb  Pb51  1  0.250  0.829  0.693  1.0
[/CIF]
.
The crystal structure described by K4Pb9 is Magnesium tetraboride-like structured and crystallizes in the monoclinic P2_1/m space group. There are five inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one Pb(1), one Pb(10), one Pb(11), one Pb(3), one Pb(4), one Pb(6), one Pb(8), and one Pb(9) atom. In the second K site, K(2) is bonded in a 7-coordinate geometry to one Pb(2), two equivalent Pb(10), two equivalent Pb(6), and two equivalent Pb(9) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to one Pb(1), one Pb(10), one Pb(2), one Pb(3), one Pb(6), one Pb(7), one Pb(8), and one Pb(9) atom. In the fourth K site, K(4) is bonded in a 8-coordinate geometry to one Pb(11), one Pb(12), one Pb(5), one Pb(6), one Pb(7), one Pb(8), and two equivalent Pb(4) atoms. In the fifth K site, K(5) is bonded in a 7-coordinate geometry to one Pb(12), one Pb(5), one Pb(7), two equivalent Pb(4), and two equivalent Pb(9) atoms. There are twelve inequivalent Pb sites. In the first Pb site, Pb(11) is bonded in a distorted body-centered cubic geometry to two equivalent K(1), two equivalent K(4), two equivalent Pb(4), and two equivalent Pb(6) atoms. In the second Pb site, Pb(12) is bonded in a 8-coordinate geometry to one K(5), two equivalent K(4), one Pb(1), two equivalent Pb(4), and two equivalent Pb(8) atoms. In the third Pb site, Pb(1) is bonded in a 9-coordinate geometry to two equivalent K(1), two equivalent K(3), one Pb(12), two equivalent Pb(6), and two equivalent Pb(8) atoms. In the fourth Pb site, Pb(2) is bonded in a 8-coordinate geometry to one K(2), two equivalent K(3), one Pb(7), two equivalent Pb(10), and two equivalent Pb(3) atoms. In the fifth Pb site, Pb(3) is bonded in a 1-coordinate geometry to one K(1), one K(3), one Pb(10), one Pb(2), one Pb(7), and one Pb(9) atom. In the sixth Pb site, Pb(4) is bonded in a 8-coordinate geometry to one K(1), one K(5), two equivalent K(4), one Pb(11), one Pb(12), one Pb(4), and one Pb(8) atom. In the seventh Pb site, Pb(5) is bonded in a 6-coordinate geometry to one K(5), two equivalent K(4), one Pb(7), and two equivalent Pb(9) atoms. In the eighth Pb site, Pb(6) is bonded in a 8-coordinate geometry to one K(1), one K(2), one K(3), one K(4), one Pb(1), one Pb(11), one Pb(6), and one Pb(8) atom. In the ninth Pb site, Pb(7) is bonded in a 9-coordinate geometry to one K(5), two equivalent K(3), two equivalent K(4), one Pb(2), one Pb(5), and two equivalent Pb(3) atoms. In the tenth Pb site, Pb(8) is bonded in a 7-coordinate geometry to one K(1), one K(3), one K(4), one Pb(1), one Pb(12), one Pb(4), and one Pb(6) atom. In the eleventh Pb site, Pb(9) is bonded in a 8-coordinate geometry to one K(1), one K(2), one K(3), one K(5), one Pb(10), one Pb(3), one Pb(5), and one Pb(9) atom. In the twelfth Pb site, Pb(10) is bonded in a 7-coordinate geometry to one K(1), one K(2), one K(3), one Pb(10), one Pb(2), one Pb(3), and one Pb(9) atom. is represented by the CIF card [CIF]
data_K4Pb9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.469
_cell_length_b   9.825
_cell_length_c   16.201
_cell_angle_alpha   76.806
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   2087.328
_cell_formula_units_Z   4
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  0.927  0.381  0.787  1.0
  K  K1  1  0.750  0.739  0.568  1.0
  K  K2  1  0.573  0.381  0.787  1.0
  K  K3  1  0.250  0.261  0.432  1.0
  K  K4  1  0.003  0.052  0.630  1.0
  K  K5  1  0.997  0.948  0.370  1.0
  K  K6  1  0.402  0.675  0.909  1.0
  K  K7  1  0.098  0.675  0.909  1.0
  K  K8  1  0.497  0.052  0.630  1.0
  K  K9  1  0.503  0.948  0.370  1.0
  K  K10  1  0.902  0.325  0.091  1.0
  K  K11  1  0.073  0.619  0.213  1.0
  K  K12  1  0.427  0.619  0.213  1.0
  K  K13  1  0.750  0.886  0.203  1.0
  K  K14  1  0.598  0.325  0.091  1.0
  K  K15  1  0.250  0.114  0.797  1.0
  Pb  Pb16  1  0.750  0.067  0.754  1.0
  Pb  Pb17  1  0.750  0.131  0.506  1.0
  Pb  Pb18  1  0.250  0.869  0.494  1.0
  Pb  Pb19  1  0.562  0.308  0.377  1.0
  Pb  Pb20  1  0.868  0.754  0.029  1.0
  Pb  Pb21  1  0.750  0.497  0.239  1.0
  Pb  Pb22  1  0.438  0.692  0.623  1.0
  Pb  Pb23  1  0.633  0.766  0.782  1.0
  Pb  Pb24  1  0.132  0.246  0.971  1.0
  Pb  Pb25  1  0.750  0.171  0.307  1.0
  Pb  Pb26  1  0.443  0.000  0.122  1.0
  Pb  Pb27  1  0.133  0.234  0.218  1.0
  Pb  Pb28  1  0.632  0.754  0.029  1.0
  Pb  Pb29  1  0.367  0.234  0.218  1.0
  Pb  Pb30  1  0.370  0.384  0.622  1.0
  Pb  Pb31  1  0.369  0.612  0.449  1.0
  Pb  Pb32  1  0.130  0.384  0.622  1.0
  Pb  Pb33  1  0.250  0.440  0.072  1.0
  Pb  Pb34  1  0.867  0.766  0.782  1.0
  Pb  Pb35  1  0.250  0.503  0.761  1.0
  Pb  Pb36  1  0.250  0.935  0.029  1.0
  Pb  Pb37  1  0.938  0.308  0.377  1.0
  Pb  Pb38  1  0.131  0.612  0.449  1.0
  Pb  Pb39  1  0.630  0.616  0.378  1.0
  Pb  Pb40  1  0.750  0.560  0.928  1.0
  Pb  Pb41  1  0.062  0.692  0.623  1.0
  Pb  Pb42  1  0.631  0.388  0.551  1.0
  Pb  Pb43  1  0.250  0.933  0.246  1.0
  Pb  Pb44  1  0.869  0.388  0.551  1.0
  Pb  Pb45  1  0.870  0.616  0.378  1.0
  Pb  Pb46  1  0.368  0.246  0.971  1.0
  Pb  Pb47  1  0.750  0.065  0.971  1.0
  Pb  Pb48  1  0.057  0.000  0.122  1.0
  Pb  Pb49  1  0.943  1.000  0.878  1.0
  Pb  Pb50  1  0.557  1.000  0.878  1.0
  Pb  Pb51  1  0.250  0.829  0.693  1.0
[/CIF]
.