Abstract
Two-photon ionization spectra of jet-cooled NH3 have been obtained in the region between the adiabatic ionization potential and the NH3+ X̃ 2A2″(0200) ionization threshold. Fairly intense np and nf Rydberg series are observed converging to selected rotational levels of the X̃ 2A2″(0100) and (0200) states. Rydberg series converging to higher vibrational thresholds and requiring vibrational autoionization by Δvi⩽−2 are also observed. Photoelectron spectroscopy reveals that many of the molecules in the latter series do not autoionize, but instead are ionized by the absorption of an additional photon. The new two-photon spectra are compared with previously reported double resonance spectra in the same energy region, providing insight into questions of the spectroscopic assignments.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
