Mass and charge transfers before contact in 40Ca +208Pb collisions

Nuclear molecules, which briefly form when nucleons from slowly colliding nuclei move under the influence of both nuclei, offer insight into reaction dynamics. Molecular single-particle states of protons and neutrons in the approach phase of the [Formula: see text]Ca + [Formula: see text]Pb collision are calculated using the two-center shell model, allowing us to understand nucleon excitations and transfers that may occur before the nuclei reach their touching configuration. Molecular single-particle spectra show that while protons in [Formula: see text] exhibit excitations, neutrons transfer from [Formula: see text] to [Formula: see text], producing neutron-rich calcium isotopes.