ELUCIDATING INTRAMOLECULAR VIBRATIONAL COUPLING MECHANISMS BY MICROWAVE SPECTROSCOPY OF SINGLE VIBRATIONALLY MIXED QUANTUM STATES - CORIOLIS AND CONFORMER INTERACTIONS IN ALLYL FLUORIDE

We have measured the rotational spectra of several molecular eigenstat es of the cis and gauche asymmetric hydride stretch in order to determ ine the nature of the weak vibrational interactions observed in these vibrational bands. The rotational spectra are measured using an infrar ed-microwave double resonance technique based on the Autler-Townes spl itting of states in a strong microwave field. From the rotational spec tra, we can detect contribution to the eigenstates from both localized structures (cis and gauche) and states of delocalized structure, or ' 'isomerization states''. Evidence of rotational transitions assigned t o isomerization states are observed in from the eigenstates prepared i n both the cis and gauche vibrational band. Furthermore, detection of Coriolis interactions in the cis band is observed. However, we do not detect any coupling between states localized around different wells of the potential (i.e., cis and gauche) suggesting that the molecule is not undergoing isomerization.