ADSORPTION OF OXYGEN IN SLIT-LIKE PORES - GRAND CANONICAL ENSEMBLE MONTE-CARLO STUDIES

The adsorption of oxygen and adsorption of homonuclear diatomic Lennard-Jones molecules having relative elongation 0.6 in slit-like pores is studied using the grand canonical Monte Carlo method of simulations for several values of the slit width. For each slit we calculate the average number of molecules and average values of the molecule-wall and molecule-molecule potential energies. The structure of the fluid is characterized by distribution functions of atoms and centres of mass, as well as by the full, angular-dependent local density. The calculations are carried out at two temperatures: T = 100 K and T = 200 K. At the lower temperature and for wider pores the phenomenon of capillary condensation is observed. We also study the changes of the structure of the adsorbed fluid during capillary condensation. The evaluated site-wall distribution functions are next used to test the application of the so-called site superposition approximation for the angular-dependent density profile.