The eigenvalues and eigenfunctions of the low-lying levels of ${\mathrm{Pb}}^{206}$ have been calculated using a singlet-even potential, and a $P_2$-type force which is known to arise when the particle states are weakly coupled to a phonon. All the neutron orbitals between $N=82\mathrm{}$ and $N=126\mathrm{}$ have been considered. The ground-state wave function is found to be in much better agreement with experiment than has been the case for previous calculations.

• Received 12 July 1967

DOI:https://doi.org/10.1103/PhysRev.168.1388