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

[Display omitted] •The newly implemented parallelized quantum–classical dynamical approach, namely, Time-Dependent Discrete Variable Representation (TDDVR) method is applied to spectroscopically important phenanthrene, acenaphthene and pyrene to illustrate their various dynamical aspects.•The four lowest singlet excited electronic states (X, A, B and C) of Compact Polycyclic Aromatic Hydrocarbons (CPAHs) are vibronically coupled through several conical intersections.•The parallel TDDVR algorithm shows almost linear scalability with increasing number of computing processors, where the complexity of Hamiltonian and increasing basis set is not a matter of concern.•First principles quantum–classical dynamical calculations are performed with the adopted Hamiltonians to obtain photoelectron (PE) spectra, zero electron kinetic energy (ZEKE), population dynamics and many other dynamical quantities.•TDDVR calculated PE and assigned ZEKE spectra of all CPAHs show good agreement with the experimental data and other available theoretical results. 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.