A molecular-dynamics study was made of the self-diffusion tensor of a Lennard-Jones-type fluid, confined within a slit pore with attractive walls. Bayesian equations were developed which modified the Liu-Harder-Berne virtual layer sampling method. An analytical solution was found for the corresponding inhomogeneous Langevin equation. The expressions found for the mean-squared displacement in the layers naturally involved a modification due to the mean force in the transverse component in terms of the anisotropic diffusion constants and mean exit time. The expression was used to fit the molecular-dynamics data to the entire survival time interval, not only for the parallel but also for the perpendicular direction. The only fitting parameter in each layer was the diffusion constant.

Molecular Dynamics and Analytical Langevin Equation Approach for the Self-Diffusion Constant of an Anisotropic Fluid. Colmenares, P.J., López, F., Olivares-Rivas, W.: Physical Review E, 2009, 80[6], 061123