2019 Volume 52 Issue 1 Pages 1-7
In solvate–solvent systems, the interactions between the constituent functional groups in the component molecular species are important for the fundamental properties, such as the molecular diffusivity and solubility. In this work, in order to evaluate the interactions at the atomic level, the binding strengths of the constituent ketone groups of four vinyl pyrrolidone analogs and methyl methacrylate to the surrounding water molecules are estimated by using the residence times of water obtained from molecular dynamics simulations. To determine the residence times, the residence rates of water are determined as a function of the elapsed time, and the obtained curves are then fitted by exponential polynomial equations. The absolute values of the correlation factors in the fitting are greater than 0.999 regardless of the miscibility of the solvate, demonstrating the validity of the estimated residence times. Additionally, the residence time is strongly correlated with the self-diffusivity of water molecules in these systems. The results indicate that the residence time is an atomic-level criterion to evaluate the affinities between the constituent groups of molecular species.
