Computer simulation in pores with rectangular cross-sections

Monte Carlo computer simulations are reported for the sorption of Ar at 90 K in several pores of different shapes. In all cases, the pore walls were modeled as perfectly flat graphitic planes that have been assembled to form pores with rectangular cross-sections characterized by having one dimension fixed at a value that allows four layers of argon in the full pore (with one exception). The second dimension of the rectangle was varied from four to eight to 12 argon atom diameters to infinite (simple slit). A pore having dimensions of 7 x 7 argon atoms was also studied. It is shown that the presence of corners in these pores has a profound effect upon their adsorptive behavior; that adsorption in the corners can be quantitatively treated in terms of one-dimensional theory; and that the remaining adsorption on the walls gives monolayer packings with liquid-like two-dimensional densities. The effect of pore shape upon capillary condensation and hysteresis is also investigated. (C) 1998 Elsevier Science Ltd. All rights reserved.