An Efficient Method for Determining Population Decay of Nonadiabatic Unimolecular Reactions

Abstract

The trajectory surface-hopping (TSH) model 1) is widely utilized for nonadiabatic reactions. Dynamical or statistical approachs are used for calculation based on it. The statistical methods avoid large-scale trajectory calculations by means of introducing dynamical assumptions in systems. The statistical methods are inherently approximate and are give more or less biased results, i.e., results calculated by statistical methods are deviate from the true values for the TSH model, while results calculated by the dynamical methods converge to the true values if computational errors and limits are neglected. Trajectory calculations can become extremely timeconsuming for large molecules. Therefore, it is desirable for a technique to obtain the results with better precision and accuracy from a certain amount of trajectory calculations. In this study, we develop an efficient method for determining unbiased population decay of nonadiabatic unimolecular dissociation of TSH model, and it is applied to a model molecular system as a numerical test.