Saturation predissociation spectroscopy: Vibrational transition moments of HF dimer

Abstract

By saturating specific rovibrational transitions in (HF)2 using a high-resolution, single-mode color center laser, the vibrational transition moments for two F–H stretches have been measured regardless of the internal state distribution of the clusters in the molecular beam. Details of the experimental procedure and data analysis are presented. A slight enhancement (∼10%) of the transition moment over the noncomplexed monomer value was observed for the proton acceptor. The proton donor transition moment was substantially enhanced by ∼100% as a result of hydrogen bonding. These results are in excellent agreement with recent theoretical studies. This method is shown to serve as a useful gauge for estimating hydrogen bond interactions within molecular clusters.