Vibrational energy relaxation of a diatomic molecule in a superfluid helium nanodroplet: influence of the nanodroplet size, interaction energy and energy gap

Abstract

The influence of the nanodroplet size, interaction potential energy and vibrational energy gap on the vibrational energy relaxation of a diatomic molecule in a superfluid helium nanodroplet has been studied theoretically for the first time.

Quantum dynamics of the Br2 (B-excited state) photodissociation in superfluid helium nanodroplets: importance of the recombination process

“…This is due to the fact that the 〈 v r 〉 results arise from the contributions of the bound and non-bound parts of the wave packet. More concretely, the former contribution is the one that generates the oscillations (and will also experience vibrational relaxation for large enough times which are well above the ones considered here 32,33 ). This is the only effect of this part of the wave packet to 〈 v r 〉 since the position is steady, i.e.…”

“…In this method, which has been previously proposed by us and applied to the related Cl 2 case, 25,26 the helium atoms are described by means of the mean field TDDFT method and the molecule is described using a time dependent quantum wave packet (WP). Besides, the common so-called Orsay-Trento (OT) phenomenological density functional (T = 0 K) 42 , including some reasonable and commonly used approximations (the backflow term and the non-local contribution to the helium correlation energy have not been considered), [25][26][27][29][30][31][32][33][34][35][43][44][45] has been used to account for the helium.…”

“…This work has been carried out employing a quantum hybrid method proposed 25 and previously applied by us (with some modifications when needed) to investigate the dynamics of several physicochemical problems involving ( 4 He) N and atoms or diatomic molecules (photodissociation, [25][26][27] atom capture, 28,29 van der Waals reaction, 30,31 vibrational relaxation, 32,33 rotational relaxation 34 and helium nanodroplet relaxation 35 ). Therefore, time dependent density functional theory (TDDFT) and standard quantum mechanics have been used to describe helium and the Br 2 molecule, respectively, analogously as in the case of the Cl 2 (B) photodissociation.…”