Pathway of D+ in sequential double ionization of D2 in an intense laser pulse

Details of the pathway for the dissociative ionization process of the ground electronic state of aligned D2+ produced from the first ionization of D2 in a short (∼100 fs) and intense (4.0x1014 W cm-2) 480 nm laser pulse are analyzed and visualized. The initial vibrational state of D2+ comes from the vertical transformation of the ground state of D2. The initial wave packet in the ground electronic state of D2+ is outgoing through a dissociation-ionization channel accompanied by a strong coupling between the 1sσg and 2pσu electronic states. We show explicitly that the transition from the coupling states 1sσg and 2pσu to the ionization state is not a direct transition, but takes place through other intermediate states having some dissociative energy that results in a relatively wide internuclear distribution of the ionization state.