Widom line of real substances

Abstract

In this work we investigate if a criterion previously found by a theoretical study using discrete potential models is suitable for the determination of the Widom line of real substances. The criterion is based on critical phenomena theory and contains implicitly the coincidence of the locus of maxima of several response functions using only the locus of two of them. Additionally, it provides a quantitative determination of the Widom line end point coordinates. The Widom line of five real substances is presented and their behavior under a two- and a three- parameter corresponding states principle is explored.