Structure and Dynamic Inhomogeneity of Liquids on the Liquid–Gas Coexistence Curve Near the Triple Point

The paper proposes a method based on a combination of the provisions of the phonon theory of liquid, V–T formalism, and Frenkel’s theory of determining the P–T parameters of a liquid system, to determine the pressure and temperature values at which the transition from a denser liquid fraction to a less dense one occurs. Its use makes it possible to analyze the motion of fluid components in joint complexes and to determine their lifetime. It is also shown that at short time intervals, regardless of the physical state of the system, the components of the liquid move as independent particles, and their motion can be represented within the framework of the vibrational-hopping diffusion model. In this paper, the developed methodology is used to study the structural and dynamic properties of argon near the triple point on the liquid–gas coexistence curve.