State-Resolved Quantum Dynamics of Photodetachment of HCO2-/DCO2- on an Accurate Global Potential Energy Surface

摘要

Full-dimensional quantum dynamics studies of the photodetachment of HCO2- and DCO2- are reported using a wave-packet Method on an accurate global potential energy surface of the neutral HOCO/HCO2 system. The Calculated phothelectron spectra reproduced both the positions and Widths of the main HCO2 and DCO2 peaks observed:in experiment. Specifically, both the (2)A(1) and B-2(2) resonance peaks of the neutral radicals were identified in our simulations thanks to the adiabatic PES that captures both the (2)A(1) and B-2(2) minima. The narrow widths and isotope effect of the lowest resonances are indicative of tunneling-facilitated predissociation. Furthermore, the dissociation product CO2 was found to be excited in both its symmetric stretching and bending modes, which are coupled Via a strong Fermi resonance, but rotationally cold, in good agreement with the recent photoelectron-photodetachment coincidence experiments.