One of the primary drawbacks of organic materials, compared to their inorganic counterparts in various optoelectronic applications, is their lower charge generation efficiency, which stems from their ...

Online congress discussing state of the art computational chemistry

Recent advances in the generation of ultrashort, few-femtosecond laser pulses in the ultraviolet–visible domain are now enabling the coherent excitation of several electronic states in neutral molecul...

Online congress discussing state of the art computational chemistry

Online congress discussing state of the art computational chemistry

Surface hopping simulations critically depend on the accuracy and robustness of the underlying electronic structure methods. Fully correlated approaches─such as CASPT2, MRCI, L-PDFT, and MRSF-TDDFT─th...

Programa China Scholarship Council-Universidad Autónoma de Madrid (CSC-UAM)

Online congress discussing state of the art computational chemistry

This Perspective reviews the use of vibronic coupling (VC) potentials in trajectory-based excited-state dynamics simulations. Originally developed to provide simplified yet physically grounded representations of nonadiabatic interactions, VC models─particularly their linear version (LVC)─have facilitated extensive investigations of photophysical and photochemical processes, in both molecular and condensed-phase systems. By effectively capturing the coupling between electronic and vibrational motions, VC models enable efficient dynamical simulations, making it feasible to investigate larger and more complex systems, for longer time scales or relying on potential energy surfaces calculated with high levels of theory. These models provide valuable insights into energy and charge transfer mechanisms following photoexcitation, shedding light on excited-state lifetimes and intricate relaxation pathways. Here, we discuss their integration with three trajectory-based computational families of methods: surface hopping, variational multiconfigurational Gaussian, and exact-factorization-derived approaches. We showcase how VC models have helped uncovering key mechanistic insights, including state-specific intersystem crossing pathways and vibrational mode selectivity. As the field progresses, VC-based approaches are expected to be increasingly combined with machine learning, anharmonic corrections, and hybrid LVC/MM frameworks, broadening their applicability to complex, flexible, and solvated environments. We highlight the advantages of VC-based potentials for trajectory-based simulations, emphasizing their computational efficiency and usefulness for benchmarking and exploring photophysical processes in molecular systems.

This Perspective reviews the use of vibronic coupling (VC) potentials in trajectory-based excited-state dynamics simulations. Originally developed to provide simplified yet physically grounded represe...

Short-in-time, broad-in-energy attosecond or few-femtosecond pulses can excite coherent superpositions of several electronic states in molecules. This results in ultrafast charge oscillations known as charge migration. A key open question in the emerging field of attochemistry is whether these electron dynamics, which due to decoherence often last only for a few femtoseconds, can influence longer-time scale nuclear rearrangements. Herein, we address this question through full-dimensional quantum dynamics simulations of the coupled electron–nuclear dynamics initiated by ionization and coherent excitation of ethylene. The simulations of this prototype organic chromophore predict electronic coherences with half-lives of less than 1 fs. Despite their brevity, these electronic coherences induce vibrational coherences along the derivative coupling vectors that persist for at least 50 fs. These results suggest that short-lived electronic coherences can impart long-lasting legacies on nuclear motion, a finding of potential importance to the interpretation of attosecond experiments and the development of strategies for attochemical control.

Simulating the coupled electronic and nuclear response of a molecule to light excitation requires the application of nonadiabatic molecular dynamics. However, when faced with a specific photophysical ...

Simulating the coupled electronic and nuclear response of a molecule to light excitation requires the application of nonadiabatic molecular dynamics. However, when faced with a specific photophysical ...