Classical dynamics of highly excited CH and CD overtones in benzene and perdeuterobenzene

Abstract

The classical decay of highly excited CH and CD overtones of benzene and perdeuterobenzene is examined by trajectory techniques. The character, mechanism, and time scale of these decays are in striking qualitative agreement with those found in the preceding quantum study by Sibert, Reinhardt, and Hynes. The classical coupling mechanism for the decay is shown to be nonlinear Fermi resonance involving the CH(D) stretch and the in-plane CCH(D) wag. The decay path is described in terms of overlapping nonlinear resonance interactions.