International audienceThe spatial dispersion of the single-nucleon wave functions is analyzed using the self-consistent mean-field framework based on nuclear energy density functionals and with the harmonic-oscillator approximation for the nuclear potential. It is shown that the dispersion depends on the radial quantum number n but displays only a very weak dependence on the orbital angular momentum. An analytic expression is derived for the localization parameter that explicitly takes into account the radial quantum number of occupied single-nucleon states. The conditions for single-nucleon localization and formation of cluster structures are fulfilled in relatively light nuclei with A≤30 and n=1 states occupied. Heavier nuclei exhibit the...