Spectral quantization of high energy transition state resonances in the H+H2 reaction

Abstract

We have discovered 13 transition state resonances for the collinear H+H2 chemical reaction on the DMBE potential surface. The resonances were identified through a hypothetical transition state spectrum, I(ω), generated using a time-dependent wave packet method. The transition state resonances are manifested as strong peaks in spectrum. The peak positions and widths give the resonance energies and widths, respectively. Since the initial wave packet used to generate the spectrum can be chosen to maximize the overlap with the resonance states, the interference of the resonance peaks with the background continuum can be minimized. The resonance energies, lifetimes, and wave functions have been extracted for all 13 resonances. Unexpectedly, the lifetimes grow significantly longer at higher energy. The resonance wave functions form a single progression built up along the asymmetric stretch coordinate. The resonances appear to be in close correspondence with resonant periodic orbits trapped in the transition state region.