Understanding nuclear quantum effects in the solvation structure and hydrogen bond dynamics of fluoride hydration using many-body potentials

Ion hydration is integral to biological functions, pharmaceutical applications, and future green-energy endeavors. Fluoride compounds in particular are known to react with water and play a major role in the stratospheric chemistry of chlorofluorocarbons. Classical molecular dynamics simulations have been able to predict numerous properties of fluoride hydration. However, classical molecular dynamics omits nuclear quantum effects arising from the presence of light hydrogen nuclei in water. Furthermore, since fluoride forms hydrogen bonds in water, it weakens the covalent OH bonds, and can lead to an enhancement in nuclear quantum effects. Thus, a complete understanding of fluoride hydration necessitates the system be treated quantum-mechanically. In this study, we employ path-integral based quantum dynamical methods along with MB-pol and MB-nrg, highly accurate data-driven many-body potentials, for water and fluoride respectively, to study the role of nuclear quantum effects in fluoride hydration. We will discuss radial distribution functions, diffusion coefficients, mean residence times, infrared spectra, and orientational correlation functions as a function of solvation shells to explain the hydration structure and dynamics of water around fluoride.