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The tracer exchange of molecules between the phase adsorbed in one-dimensional channels and the surrounding gas phase by molecular dynamics simulations is studied. It is seen that equilibrium concentration is reached faster at the boundaries and slower in the middle part of the channel in the case of single-file diffusion, which can be explained by the mechanisms of the normal diffusion laws and that which admits additional displacements causing an accelerated particle exchange.

The dynamical and structural properties of water molecules inside the siliceous ZSM-5 at various loadings are presented with the aim of obtaining an understanding at the molecular level. The ab initio fitted water/silicalite-1 model based on quantum chemical methods is used and the results reveal that the water structure inside the silicalite-1 cages changes dramatically as a function of loading and that the probability of water molecules residing in a straight channel is always higher than that of residing in the sinusoidal channels.

The correlation between the principal tensor elements of diffusion in MFI-type zeolites such as silicalite-1 and ZSM-5 may be substantially affected by memory effects. Extensive molecular dynamics (MD) simulations of the molecular diffusion of methane in zeolite silicalite-1 are analyzed on the basis of the concept of memory-dependent molecular propagation.

A study was conducted to determine an approximation for the self-part of the van Hove function. The self-part of the function was obtained by MD simulation for the diffusion of methane in ZK4 and silicalite. The intermediate scattering function was then realized by Fourier transform in space of the van Hove function. Findings indicated that Fourier transform in yield generates the dynamic structure factor which can be examined against quasi-elastic neutron results.

A study was conducted to analyze the diffusion of a mixture of methane and xenon in the zeolite silicalite using molecular dynamics simulations and pulsed field gradient nuclear magnetic resonance. The interactions were modeled by 12-6 Lennard-Jones pair potentials. Experimental results indicated that the limited rnage of the spin-echo attenuation and the finite contribution of long-range and restricted diffusion hindered the determination of the principal values of the diffusion tensor.