Laser induced dispersed fluorescence spectroscopy of 107 vibronic levels of NO2 ranging from 12 000 to 17 600 cm−1

We report the laser induced dispersed fluorescence spectra (LIDFS) of NO2 recorded when exciting 107 vibronic levels lying between 11 961 and 17 627 cm−1. These levels result from the vibronic interactions between the highly excited vibrational levels of the electronic ground state, X 2A1, and the isoenergetic levels of the electronic excited state, A 2B2. One observes that the intensity patterns of almost half of the LIDFS can be interpreted in terms of Franck–Condon factors (FCFs) between a single bright parent level belonging to A 2B2 and the low-lying vibrational levels of X 2A1. This means that the vibronic interactions occurring between the vibrational levels of X 2A1 and A 2B2 are not strong enough to systematically mix together several bright parent states of A 2B2. We have also found that vibronic eigenstates scattering over several hundreds of cm−1 can be assigned to the same bright parent state. However, these features, which are characteristic of individual vibronic levels, must be faced wi...

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