Critical scaling in the theory of real fluids

Abstract

An approach developed in the author’s recent paper [V.N. Bondarev, Phys. Rev. E 77, R050103 (2008)], where the independent calculation of three critical exponents for a fluid was demonstrated, is generalized to the case of the critical isotherm. This has allowed us to calculate, independently, three more critical exponents: δ = 4, μ = 5/12, and α = 1/8. These “non-classical” values are in good agreement with those determined experimentally and are rather close to the 3-dimensional Ising ones. In addition, on the basis of this approach a solution of the so-called Yang-Yang problem concerning the “pressure” and the “chemical potential” contributions to the critical singularity of the isochoric heat capacity of a fluid is proposed. Also, the so-called “corrections to scaling” terms are considered in the framework of the developed theory and the corresponding exponents at the critical isochore and the critical isotherm are calculated. The results obtained provide a natural perspective for including the non-classical (of the Ising-type) description of fluid critical properties into the conventional theory of liquids.