Nonadiabatic events involving relaxation process within the manifolds of coupled electronic states, such as internal conversion and intersystem crossing, became a very active area of research. In the last few decades, concentrated efforts have been devoted to accurately predict the rate of nonadiabatic reactions. These rates can be calculated using time-independent and time-dependent approaches. Nonadiabatic transition state theory (NA-TST), one of the leading time-independent statistical approaches, requires the local knowledge of potential energy surfaces (PESs) and assumes that the transitions between electronic states always occur in the vicinity of a minimum energy crossing point. In contrast, the time-dependent quantum dynamics approach based on solving the Schrödinger equations for the nuclear motion on the multiple coupled electronic states, can account for the transitions occurring in different regions of the PESs. In this talk, we will present our model study for predicting nonadiabatic reaction rates using NA-TST, as well as “exact” quantum dynamics and “on-the-fly” multiple spawning methods. The simple PES models used in this study mimic the different topographies of state crossings. We will compare and analyze the reaction rates predicted by different nonadiabatic dynamics and statistical theories.

On the rates of nonadiabatic reactions: Model study and comparison between statistical and dynamics approaches

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.