Intramolecular vibrational relaxation in the S state of s-tetrazine–X (X=Ar, Kr, Xe)

Publisher Website
Google Scholar
Abstract
A triple resonance experiment with fluorescence detection has been carried out to investigate the spectroscopy and intramolecular dynamics of the van der Waals molecules s‐tetrazine–X (X=Ar, Kr, Xe) with vibrational energies from 1250 to 2210 cm−1 in the ground electronic state (S0). Vibrational band shifts in S0 van der Waals molecules are usually on the order of 1 cm−1, and most relaxation lifetimes are longer than 15 ns. Comparison with published data for intramolecular vibrational redistribution in the S1 electronic state indicates a strong influence of the electronic structure of the aromatic ring on the dissociation dynamics, in clear contradiction to statistical models which have been advanced previously. A perturbation theory treatment supports the existence of a correlation between vibrational band shifts and dissociation dynamics, and rationalizes qualitatively all the peculiar observations for this class of van der Waals molecules.