Dynamic solvation fields: a paradigm shift in solvent effects on chemical reactivity

Abstract

Traditional solvent descriptors—such as dielectric constant, donor number, or polarity scales—reduce complex, fluctuating environments to static averages. While valuable for capturing bulk trends, these parameters fail to account for the localized, time-resolved interactions that govern many chemical transformations. This perspective argues for a conceptual shift: treating solvents as dynamic solvation fields, characterized by fluctuating local structure, evolving electric fields, and time-dependent response functions. Drawing on a synthesis of experimental, computational, and theoretical work from 2015–2025, we show how solvent dynamics modulate transition state stabilization, steer nonequilibrium reactivity, and reshape interfacial chemical processes. We critically examine the limitations of continuum and linear-response models and highlight emerging tools—from ultrafast spectroscopy to machine-learned potentials—that expose the active role of the solvent in chemistry. Finally, we propose a conceptual framework for a general theory of dynamic solvation fields, with implications for catalysis, nucleation, and thin-film formation. This approach offers a more faithful and predictive understanding of solvent effects in modern physical chemistry.