Stimulated Raman spectroscopic study on intermolecular vibrations of size-selected benzonitrile clusters

Abstract:

Low frequency intermolecular vibrations of benzonitrile-(H₂O)_{n = 1 - 3}, -(CH₃OH)_{n = 1 - 3}, and -(CHCl₃)_{n = 1 - 3} clusters were observed by stimulated Raman - UV double resonance spectroscopy combined with fluorescence detection. The Raman active vibrations, which appear in the region from 5 to 50 cm^-1, exhibit characteristic frequency shifts depending on the cluster structure and on the cluster size. In benzonitrile-(H₂O)_{n = 1 - 3} and -(CH₃OH)_{n = 1 - 3}, the lowest frequency band showed a lower frequency shift with an increase of the number of solvent molecules. On the other hand, that of benzonitrile-(CHCl₃)_{n = 1 - 3} showed a shift to the higher frequency side. Their characteristic shifts are discussed based on the structure of the clusters.