Time-dependent pair distribution functions based on Smoluchowski equation and application to an electrolyte solution.

Time-dependent pair distribution function characterizes the diffusion of pairs of molecules in liquids. In the diffusion regime, the function is described with three-dimensional Smoluchowski equation. We propose a scheme to numerically calculate the function between polyatomic and monoatomic species based on the Smoluchowski equation. The present scheme is successfully applied to the diffusion of Ar-Ar pair in liquid Ar and ethylene carbonate (EC)-Li+ pair in 1 M LiPF6 /EC electrolyte solution. © 2018 Wiley Periodicals, Inc.