Resonance enhancement effects in coherent two-photon ionization of CH3I

Abstract

One-color two-photon zero kinetic energy (ZEKE)-spectra of CH3I were obtained via an intermediate resonant state. In contrast to one-photon spectra an intense progression in the totally symmetric C–I stretching mode ν3+ is observed. The observation can be explained by a resonant-Raman like enhancement in the intermediate dissociative state.