COMPUTATIONAL STUDY OF MANY-DIMENSIONAL QUANTUM VIBRATIONAL-ENERGY REDISTRIBUTION .2. STATISTICS OF THE SPECTRUM WITH DYNAMICAL IMPLICATIONS

We continue a study in which we statistically analyze the dynamics of vibrational energy flow in a model system of anharmonic oscillators wh ich are nonlinearly coupled, with a local topology. Average spectra ar e obtained from individual spectra of many basis states of similar ene rgy, for different values of the magnitude of the coupling between sta tes. The survival probabilities of the density are then determined fro m the average spectra. When the average fluctuation in spectral intens ities is small then the density survival probability closely follows t he average survival probability presented in our earlier paper for sho rt times. For longer times, when the average survival probability show s a power law decay, this decay does not appear in the density surviva l probability. In addition, when spectral fluctuations are large, the two survival probabilities differ strongly. (C) 1997 American Institut e of Physics.