Solvation Effects on Reactive Intermediates: The Benzyl Radical and Its Clusterswith Ar, N2, CH4, C2H6, and C3H8

摘要

Mass resolved excitation spectra are presented for the benzyl radical and itsclusters with Ar, N2, CH4, C2H6, and C3H8. The cluster spectra exhibit small red shifts (< 50 cm-1) relative to the unclustered benzyl radical for the D sub 1 (1(2) A sub 2) reverse transition D sub 0 (1(2) B sub 2) and D sub 2 (2(2) B sub 2) reverse transition D sub 0 (1(2) B sub 2) electronic transition regions. A unique set of low energy van der Waals modes is observed for these clusters for each excited electronic state investigated. The cluster spectra also reveal significant vibronic coupling between the two excited electronic states of the benzyl radical, as evidenced by a single vibrational predissociation threshold for each cluster. Ab initio calculations are performed on the benzyl radical to examine excited electronic state structure, predict transition energies, estimate ionization energy, and determine partial atomic charges in the electronic states of interest. The resulting partial charges are used in empirical atom-atom potential energy calculations to aid in the understanding of cluster spectroscopic shifts, binding energies, and van der Waals modes....