Coupled Electronic and Structural Relaxation Pathways in the Postexcitation Dynamics of Rydberg States of ${\mathrm{BaAr}}_N$ Clusters

We investigate, theoretically, the joint relaxation of orbital and structure in postexcitation dynamics of Rydberg states of cluster ${\mathrm{BaAr}}_N$ ($N=250$). Mixed quantum-classical dynamics is used to account for the nonadiabatic transitions among more than 160 electronic states, represented via a diatomics-in-molecules Hamiltonian. The simulation illustrates the complex multistep relaxation processes and provides detailed insight in the mechanisms contributing to the final-time experimental photoelectron spectrum.

Figure 1

Time evolutions of the Ba-to-closest-Ar distance (left) and of the Ba-to-center-of-mass of the Ar cluster distance (right) (evaporated Ar atoms are excluded when calculating the center of mass of the cluster). The data in the lowest panels are sorted according to the final channels and averaged between 20 and 21 ps.

Figure 2

Time evolution of the population of the adiabatic states labeled by their energy ordering number. Increasing populations from blue to red.

Figure 3

Time evolution of the mean-field energies distribution.

Figure 4

Long time photoelectron spectra averaged in the interval 18–20 ps [green: experiment [12], blue: theory (arbitrary units)].