Photophysics of Solvated Molecules: Computational Protocol Combining Nuclear Ensemble and Nonequilibrium State-Specific Solvation Methods
Leonardo Evaristo de Sousa, Piotr de Silva
Abstract
Efficient calculations of the photophysical properties of molecules are essential for both understanding experimental results and accelerating materials discovery through computational simulations. However, to achieve accurate results, the effects of the surrounding medium must be taken into account. Here, we present a computational protocol that combines the nuclear ensemble method with a nonequilibrium state-specific polarizable continuum model to simulate absorption, fluorescence, phosphorescence, and intersystem crossing processes. Additionally, we introduced an extrapolation strategy that enables predictions for multiple solvents without incurring additional computational costs. We demonstrate the method's effectiveness by modeling the photophysical properties of a molecule that exhibits thermally activated delayed fluorescence, showcasing how these properties vary with solvent polarity. We also provide insight into the relationship between the solvent and photophysics by using ensemble analysis to rationalize simulation results. Furthermore, we introduce a metric for the intensity of the charge transfer character of electronic states and demonstrate how vibrations can significantly mix the electronic character of excited states. Overall, this work presents a computational approach that offers new insights into the photophysics of molecules and has the potential to advance materials discovery.