Relaxation dynamics of helium nanodroplets after photodissociation of a dopant homonuclear diatomic molecule. The case of Cl2@(4He)N

Abstract

To investigate the quantum dynamics of the relaxation process of excited helium nanodroplets, ⁴He_N, arising from the photodissociation of Cl₂ embedded molecules (B ← X electronic transition), here we have performed a time dependent density functional theory (TDDFT) study considering nanodroplets of different sizes (N = 50, 100, 200, 300 and 500), extending a previous study which was centered on the photodissociation step. The relaxation process takes place in the timescale of several hundred picoseconds and a simple dependence of this process on time has been found. The results have been satisfactorily analyzed in terms of a phenomenological model proposed here and also by applying the Rice–Ramsperger–Kassel (RRK) statistical chemical kinetic model for unimolecular reactions. From what we know, this is the first time that the dynamics of these de-excitation processes has been studied, opening up a window for understanding them. We expect that this work will encourage further research on this little known but interesting phenomenon.