Homo- and heteronuclear alkali metal trimers formed on helium nanodroplets. II. Femtosecond spectroscopy and spectra assignments

TL;DR

This study uses femtosecond spectroscopy to analyze homo- and heteronuclear alkali metal trimers on helium nanodroplets, assigning vibrational spectra through comparison with advanced ab initio calculations.

Contribution

It provides detailed vibrational spectra and assignments for alkali trimers, incorporating complex Jahn-Teller and spin-orbit effects, advancing understanding of their electronic structure.

Findings

Good agreement between experimental spectra and theoretical calculations.

Identification of vibrational states in various electronic states.

Insights into vibronic coupling effects in heavy alkali molecules.

Abstract

Homo- and heteronuclear alkali quartet trimers of the type K_{3-n}Rb_{n} (n=0,1,2,3) formed on helium nanodroplets are probed by one-color femtosecond photoionization spectroscopy. The obtained requencies are assigned to vibrations in different electronic states by comparison to high level ab initio calculations of the involved potentials including pronounced Jahn-Teller and spin-orbit couplings. Despite the fact that the resulting complex vibronic structure of the heavy alkali molecules complicates the comparison of experiment and theory we find good agreement for many of the observed lines for all species.