title: Photoelectron spectroscopy of ammonia via a fast predissociative state
abstract: We report a study on resonance enhanced multiphoton ionization photoelectron spectroscopy (REMPI-PES) involving the fast predissociative A state of ammonia, using nano- and femtosecond lasers. The multiphoton scheme involves (1 + 1), (2 + 2), (2 + 2) + 1 and (2 + 2) + 2 photon processes. We have found a progression of stretching vibrations v1 in the PE spectrum when pumping NH3 A v2 = 0, 1 and 3 as intermediate states. The stretching vibration intensity distributions in the photoelectron spectrum are calculated by using the Chebychev method of the wavepacket propagation. The femtosecond spectrum shows a similar feature to the nanosecond spectrum. However, high laser power also causes band broadening and shifting effect as well as above threshold multiphoton ionization.
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, China.
authors.initials: J
authors.lastname: Xie
authors.initials: B
authors.lastname: Jiang
authors.initials: G
authors.lastname: Li
authors.initials: S
authors.lastname: Yang
authors.initials: J
authors.lastname: Xu
authors.initials: G
authors.lastname: Sha
authors.initials: D
authors.lastname: Xu
authors.initials: N
authors.lastname: Lou
authors.initials: C
authors.lastname: Zhang