Heat Capacities of Argon in the Two—Dimensional Critical Region

Publisher Website
Google Scholar
Abstract
Heat capacities of argon adsorbed on a layer of xenon which had been preadsorbed on a graphitized carbon black were measured from 50°—80°K. The surface was characterized by determining adsorption isotherms and heats of adsorption. It was found that these data were equivalent to those obtained by other workers. A maximum in the heat capacity of one-half monolayer of adsorbed argon was observed at 72°K. Since the analysis of the isotherm data indicates that this system should have a two-dimensional critical point at a temperature close to the temperature of the maximum, it is concluded that the experimental curve corresponds to that for a two-dimensional film at its critical density. The data are compared with theoretical calculations based on the lattice gas model and it is found that the experimental curve is not as sharply peaked as the theoretical. Possible reasons for this discrepancy are discussed.

This publication has 9 references indexed in Scilit: