The ion activated attractive patchy particles model and its application to the liquid-vapour phase transitions

TL;DR

This paper extends a patchy particle model to include ion activation and site repulsion, analyzing its impact on liquid-vapor phase transitions to better understand experimental observations in protein solutions.

Contribution

The study introduces a modified ion-activated patchy particle model with site repulsion effects and analyzes its phase behavior using numerical methods.

Findings

Inclusion of site repulsion alters the phase diagram significantly.

Model parameters critically influence the liquid-vapor coexistence region.

Enhanced model helps interpret experimental phase behavior of protein solutions.

Abstract

Patchy particles are an intriguing subject of study and indeed a model system in the field of soft matter physics. In recent years, patchy particle models have been applied to describe a wide variety of systems, including colloidal crystals, macromolecular interactions, liquid crystals, and nanoparticle assemblies. Given the importance of the topic, rationalizing and capturing the basic features of these models is crucial to their correct application in specific systems. In this study, we extend the ion-activated attractive patchy particles model previously employed to elucidate the phase behavior of protein solutions in the presence of trivalent salts. Our extension incorporates the effect of repulsion between unoccupied and occupied binding sites, depicted as patches. Furthermore, we examine the influence of model parameters on the liquid-vapor coexistence region within the phase diagram, employing numerical methods. A deeper understanding of this model will facilitate a better comprehension of the effects observed in experiments.