A comparative multi-state multi-dimensional quantum-classical dynamics on compact polycyclic aromatic hydrocarbons (CPAHs) by parallel TDDVR method

Abstract

The newly implemented parallelized quantum–classical dynamical approach, namely, Time Dependent Discrete Variable Representation (TDDVR) method is applied to the spectroscopically important phenanthrene, acenaphthene and pyrene, where several conical intersections exist in their four lowest singlet excited electronic states (X, A, B and C), to illustrate their various dynamical aspects. This parallel version shows almost linear scalability with increasing number of computing processors. First principles dynamics is performed to the adopted Hamiltonians to obtain photoelectron (PE) spectra, zero electron kinetic energy (ZEKE) spectra, population dynamics and many other dynamical observables. The reduced densities of the wave packet (WP) in coupled electronic surfaces are used to elucidate the intrinsic dynamical features. The TDDVR calculated PE and assigned ZEKE spectra of all CPAHs are found to be good agreement with the previous experimental data and other available theoretical results.