Phase coexistence in the hard-sphere Yukawa chain fluid with chain length polydispersity: High temperature approximation

TL;DR

This paper uses high temperature approximation to analyze phase coexistence in polydisperse hard-sphere Yukawa chain fluids, revealing that the model's thermodynamics depend on a finite set of moments, enabling complete phase diagram calculations.

Contribution

It demonstrates that the polydisperse Yukawa chain fluid model is a truncatable free energy model within HTA, allowing comprehensive phase diagram analysis.

Findings

Calculated complete phase diagrams including cloud and shadow curves.

Showed the model's thermodynamics depend on a finite number of moments.

Analyzed chain length distribution functions of coexisting phases.

Abstract

High temperature approximation (HTA) is used to describe the phase behavior of polydisperse multi-Yukawa hard-sphere chain fluid mixtures with chain length polydispersity. It is demonstrated that in the frames of the HTA the model belongs to the class of ``truncatable free energy models'', i.e. the models with thermodynamical properties (Helmholtz free energy, chemical potential and pressure) defined by the finite number of generalized moments. Using this property we were able to calculate the complete phase diagram (i.e., cloud and shadow curves as well as binodals) and chain length distribution functions of the coexisting phases.