Effect of the ratio of length of sphere to length of cylinder on adsorption and self-diffusion in a ‘sphere-cylinder’ micropore

Abstract

MD simulation results are reported for the effect of the ratio of the length of sphere to length of cylinder (A/L) on the self-diffusion of Lennard-Jones fluids confined in a ‘sphere-cylinder’ micropore in which spheres are interconnected through cylindrical sections. The radius of the sphere, measured from the centre of the pore to the centre of the wall atom, was R_s= 2.35σ and that of the cylinder was R_c= 2σ. The ratio A/L was varied between 0.0–2.0. The results include the temperature dependence of the self-diffusion coefficient parallel to the pore walls (D^*_∥) at two densities n_pσ³= 0.82 and 0.40, and two temperatures kT/ε= 0.50 and 1.49. The behaviour of the mean-square displacement (MSD) and velocity auto-correlation function (VACF) normal to the pore walls is also discussed.