The time-dependent quantum wave packet approach to the electronically nonadiabatic processes in chemical reactions

Abstract

The time-dependent quantum wave packet approach has been improved and formulated to treat the multiple surface problems and thus provided a new simple, yet a clear quantum picture for interpreting the reaction mechanism underlying the nonadiabatic dynamical processes. The method keeps the salient feature of the original quantum wave packet theory developed for single surface problems, i.e. the introduction of the absorbing potential and the grid basis including the discrete variable representation and the fast Fourier transformation, which makes the present methodology a very efficient implement for the nonadiabatic quantum scattering calculations. Here, we review the theoretical basis of this approach and its applications to the fundamental triatomic chemical reactions, the latter include the nonadiabatic dynamics calculations on the F + H2, F + HD, F + D2, O(1D) + N2, O(3P, 1D) + H2, D+ + H2, and H+ + D2 reactions. We also present a thorough historical overview of the theoretically nonadiabatic dynamical investigations particularly on the triatomic systems, and show how the time-dependent wave packet approach complements the time-independent quantum scattering theory. Contents PAGE 1. Introduction 202 2. Historical overview 203 3. Time-dependent quantum wave packet approach for A + BC reaction 206 3.1. Propagation of the wave function 206 3.2. Preparation of the initial wave function 208 3.3. Analysis of the final wave function 209 4. Examples 210 4.1. Nonadiabatic effects on the reaction mechanism of F(2P3/2,2P1/2) + H297 210 4.2. The reactivity of the ground and the excited spin state F(2P3/2,2P1/2) atoms with D298 212 4.3. Nonadiabatic investigation on the F(2P3/2,2P1/2) + HD reaction 99,100 213 4.4. Electronic quenching process in the O(1D) + N2 → O(3P) + N2 reaction 101 218 4.5. The intersystem crossing effects in the O(3P,1D) + H2 reaction 102 221 4.6. Nonadiabatic quantum calculations on the D+ + H2 reaction 103 225 4.7. Nonadiabatic investigation on the H+ + D2 reaction 104 229 5. Conclusions 231 Acknowledgments 233 References 233