Change of shell structure and magnetic moments of odd-Ndeformed nuclei towards the neutron drip line

Examples of the change of neutron shell structure in both weakly bound and resonant neutron one-particle levels in nuclei towards the neutron drip line are exhibited. It is shown that the shell-structure change due to the weak binding may lead to the deformation of those nuclei with the neutron numbers N ≈ 8, 20, 28 and 40, which are known to be magic numbers in stable nuclei. Nuclei in the ‘island of inversion’ are most easily and in a simple manner understood in terms of deformation. As an example of spectroscopic properties other than single-particle energies, magnetic moments of some weakly bound possibly deformed odd- N nuclei with neutron numbers close to those traditional magic numbers are given, which are calculated using the wavefunction of the last odd particle in deformed Woods–Saxon potentials.