Efficient Semiclassical Evaluation of Electronic Coherences in Polyatomic Molecules

TL;DR

This paper reviews a new efficient semiclassical method for simulating electronic coherences in polyatomic molecules, combining ab initio electronic structure calculations with nuclear wave packet dynamics to understand decoherence and revival phenomena.

Contribution

It introduces a computationally efficient approach that couples accurate electronic structure simulations with semiclassical nuclear dynamics for polyatomic molecules.

Findings

Method effectively captures electronic coherence dynamics.

Reveals physical mechanisms of decoherence and revival.

Reduces computational cost of simulations.

Abstract

Exposing a molecule to intense light pulses may bring this molecule to a nonstationary quantum state, thus launching correlated dynamics of electronic and nuclear subsystems. Although much had been achieved in the understanding of fundamental physics behind the electron-nuclear interactions and dynamics, accurate numerical simulations of light-induced processes taking place in polyatomic molecules remain a formidable challenge. Here, we review a recently developed theoretical approach for evaluating electronic coherences in molecules, in which the ultrafast electronic dynamics is coupled to nuclear motion. The presented technique, which combines accurate ab initio on-the-fly simulations of electronic structure with efficient semiclassical procedure to compute the dynamics of nuclear wave packets, is not only computationally efficient, but also can help shed light on the underlying physical mechanisms of decoherence and revival of the electronic coherences driven by nuclear rearrangement.