Population and decay of the ArICl(ion-pair states) van der Waals complexes

Abstract

The article presents the analysis of the ArICl(IP,v_IP,n_IP) population and decay at energies lower than the ArICl(E,v_E= 0,n_E) dissociation limit (IP = E0⁺, $D^{\mathrm{\prime }}2$, β1), v_IP = 0, 1, n_IP are quantum numbers of the van der Waals (vdW) modes). It shows that the ArICl(IP,v_IP,n_IP) lifetimes determined at spectral ranges where the ArICl(E→X, $D^{\mathrm{\prime }}\to A^{\mathrm{\prime }}$, and β→A) luminescence takes place, are the same, τ = 20.3 ± 1.0 ns, i.e. strongly mixed complex states are populated in the ArICl(IP,v_IP,n_IP ← A,v_A,n_A) transitions, and principal channel of the complex decay is emission. We have estimated the ArICl(E0⁺,v_E= 0) binding energy and studied the ArICl(IP,v_IP,n_IP) population and decay at energies higher than the ArICl(E,v_E= 0,n_E) dissociation limit. Our research shows that the ArICl(IP,v_IP,n_IP) wave functions corresponding to specific n_IP vdW mode depend on the mode, but they are approximately constant in some spectral ranges. The ArICl(IP,v_IP,n_IP) complex decays to free ICl(E0⁺,v_E, $D^{\mathrm{\prime }}2,v_{D^{\mathrm{\prime }}}$ and β1,v_β) molecules. We have determined the probabilities of these decay channels and shown that all the ICl(IP) states are mixed under the action of the Ar atom, i.e. this atom does not behave in the ArICl(IP,v_IP,n_IP) complexes as a ‘spectator’ as it occurs in the RgI₂(IP) states.

GRAPHICAL ABSTRACT

KEYWORDS:

• van der Waals complexes
• two-step laser excitation
• supersonic molecular beam
• decay
• luminescence

Acknowledgements

The authors acknowledge the Russian Foundation for Basic Researches for grant 19-03-00148a

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.