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The performance of the established density functional theory is tested by carrying out Grand canonical ensemble Monte Carlo (GCMC) simulations to obtain the density profiles and adsorption isotherms of the hard-core multi-Yukawa fluid in the slitlike pore at different temperatures and densities. Both the DFT and the GCMC simulations predict the depletion of the multi-Yukawa fluid near a nonattractive wall.

A density functional theory is used to investigate the effects of polymer monomer-monomer and monomer-wall attractions on the density profile, chain configuration and equilibrium capillary phase transition of a freely jointed multi-Yukawa fluid confined in a slitlike pore. The equilibrium capillary phase transition of the polymeric fluid in the hard slitlike pore occurs at a higher chemical potential than in bulk condition, but as the attraction of the pore wall is increased, the chemical potential for equilibrium capillary phase transition becomes lower than that for bulk vapor-liquid equilibrium.

Two modified versions of the Elementary Physical Model (EPM) for supercritical carbon dioxide is proposed and their validities are affirmed by computing the thermodynamic properties and dielectric constant up to 910 kg/m(super 3) with use of canonical ensemble Monte Carlo simulation. As the distance between two molecules increases, the preferred orientations disappear quickly and all the results are in good agreement with the prior ab initio calculation.

Grand canonical ensemble Monte Carlo simulation and a density functional theory (DFT) were used to investigate the structures of attractive and repulsive hard-core Yukawa (HCY) fluids near a wall as well as the radical distribution function of the bulk hard core Yukawa fluids. Comparisons with the results from the Monte Carlo simulations show that the density functional theory provides accurate density profiles for both attractive and repulsive for attractive HCY fluid near a wall.

Because of the increasing interest in studying the phenomenon exhibited by charge-stabilized colloidal suspensions in confining geometry, we present a density functional theory (DFT) for a hard-core multi-Yukawa fluid. The excess Helmholtz free-energy functional is constructed by using the modified fundamental measure theory and Rosenfeld's perturbative method, in which the bulk direct correlation function is obtained from the first-order mean spherical approximation. To validate the established theory, grand canonical ensemble Monte Carlo (GCMC) simulations are carried out to determine the density profiles and surface excesses of multi-Yukawa fluid in a slitlike pore. Comparisons of the theoretical results with the GCMC data suggest that the present DFT gives very accurate density profiles and surface excesses of multi-Yukawa fluid in the slitlike pore as well as the radial distribution functions of the bulk fluid. Both the DFT and the GCMC simulations predict the depletion of the multi-Yukawa fluid near a nonattractive wall, while the mean-field theory fails to describe this depletion in some cases. Because the simple form of the direct correlation function is used, the present DFT is computationally as efficient as the mean-field theory, but reproduces the simulation data much better than the mean-field theory. [ABSTRACT FROM AUTHOR]