title: Revealing photofragmentation dynamics through interactions between Rydberg states: REMPI of HI as a case study.
abstract: High energy regions of molecular electronic states are largely characterized by the nature and involvement of Rydberg states. Whereas there are a number of observed dynamical processes that are due to interactions between Rydberg and valence states, reports on the corresponding effect of Rydberg-Rydberg state interaction in the literature are scarce. Here we report a detailed characterization of the effects of interactions between two Rydberg states on photofragmentation processes, for a hydrogen halide molecule. Perturbation effects, showing as rotational line shifts, intensity alterations and line-broadenings in REMPI spectra of HI, for two-photon resonance excitations to the j(3)Σ(-)(0(+); v' = 0) and k(3)Π1(v' = 2) Rydberg states, are analyzed. The data reveal pathways of further photofragmentation processes involving photodissociation, autoionization and photoionization affected by the Rydberg-Rydberg state interactions as well as the involvement of other states, close in energy. Detailed mechanisms of the involved processes are proposed.
authors.affiliation: Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavík, Iceland. agust@hi.is.
authors.forename: Helgi Rafn
authors.initials: HR
authors.lastname: Hróðmarsson
authors.affiliation: Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavík, Iceland. agust@hi.is.
authors.forename: Ágúst
authors.initials: Á
authors.lastname: Kvaran