ABSTRACT

Resonant two-photon ionization (R2PI) spectroscopy in conjunction with supersonic jet and mass detection techniques can be used for simultaneous detection of molecular species in a mixture. The well-resolved spectral features may be referred as the fingerprints of each species and used for molecular identification. Each spectral band is related to a particular vibrational pattern of the selected species in the electronically excited state. These vibronic states may be used as the intermediate levels for the successive excitation, followed by pulsed field ionization. The two-color resonant two-photon excitation mass analyzed threshold ionization (MATI) experiments then lead to precise determination in the ionization energy and the vibrational features of the corresponding cation of the selected species. The observed MATI bands can also be referred as the fingerprints of the cation.