Visualize the vibronic coupling in Auger final states in N2 molecule

Vibronic coupling is a critical mechanism in chemical reactions. However, its quantitative evaluation is challenging due to mathematical complexity and programming difficulty, and its experimental proof is often elusive due to overlap among neighboring states. Here, after exciting a vibrational level (v = 0, 1, 2) of the intermediate N 1s -> pi*(g) core-excited state in N-2 molecules, we separate the resonant Auger decay channels that lead to the lowest dissociation limit in the two-dimensional energy correlation maps. From three kinetic energy release spectra of these channels at different vibrational quantum numbers, we give the first experimental proof of the vibronic coupling between two resonant Auger final states 1(2) Pi(g) and 2 (2) Pi(g).

Automated summary

Vibronic coupling, a critical mechanism in chemical reactions, is challenging to quantitatively evaluate and experimentally prove. In this study, we separated resonant Auger decay channels leading to the lowest dissociation limit in N-2 molecules by exciting a vibrational level of the intermediate N 1s -> pi*(g) core-excited state. By analyzing three kinetic energy release spectra at different vibrational quantum numbers, we provide the first experimental proof of vibronic coupling between two resonant Auger final states, 1(2) Pi(g) and 2 (2) Pi(g).