Common behavior of the critical properties of the 2D and 3D square-well fluids

Abstract

We have analyzed the behavior of the critical properties and second virial coefficient of the square well fluids in two (2D) and three dimensions (3D) as a function of the interaction range. In both systems, the critical density shows an oscillating-like behavior as the interaction range increases. The second virial coefficient evaluated at the critical temperature as a function of the interaction range shows a general behavior for both cases, and quite surprisingly, there is a minimum of this parameter, for the 2D and 3D fluids, located approximately at the same interaction range. These findings are discussed in terms of the structure of the fluids, via the analysis of the radial distribution function evaluated at the critical point.