Classical dynamics of multiphoton dissociation for a model system

A classical trajectory analysis of multiphoton dissociation on a model two-dimensional anharmonic potential surface is presented. Six categories of trajectory motion were found, and the degree of “instability” within each type was analyzed in terms of power spectra and exponential separation of neighboring phase points. The dissociation probability was studied as a function of laser intensity and frequency. In addition, the translational energy spectrum of the photofragments was analyzed on the basis of several statistical theories. Good agreement with RRKM theory was found for the final partitioning between translational and vibrational energy.