Semiclassical modeling of Rydberg wave-packet dynamics in diatomic molecules: Average decoupling theory

The semiclassical dynamics of Rydberg electronic wave packets in diatomic molecules is investigated using a sum over classical trajectories method, which is based on the semiclassical form of Feynman’s path integral. Our approach allows us to calculate intramolecular energy redistribution rates based on averaging of coupling parameters over classical trajectories associated with time-dependent parts of the overall system that exhibit different periodicities. The accuracy of our method is tested against perturbation theory and good agreement is obtained. A resonance structure in the computed autocorrelation function has also been observed in the case of rotating nuclei, when the periods of the classical trajectories of the electron match an integer multiple of the rotational period. This has previously been called the “stroboscopic” effect.