Theory of the Heterophase Fluctuations in the Vicinity of Gas-Liquid Critical Point

Abstract

A theory of the heterophase fluctuations in the vicinity of the gas-liquid critical point is developed. The formulated fluctuon model of heterophase fluctuations is genetically connected with the Frenkel model but includes description of the fluctuaton interaction. As a result a mean-field theory of the heterophase fluid in critical and overcritical region is obtained. Solutions of the deduced equation of state describe thermodynamics and heterophase structure of fluid. It is shown that the continuation of the gas-liquid coexistence curve in the overcritical region is the Widom line on which the constant-pressure heat capacity has a maximum and diverges when temperature approaches the critical point.