Active Particles in Explicit Solvent: Dynamics of clustering for alignment interaction

TL;DR

This study investigates how active particles in an explicit solvent form clusters, highlighting the roles of activity and hydrodynamics using hybrid simulation methods to understand clustering dynamics.

Contribution

It introduces a hybrid simulation approach combining molecular dynamics and multi-particle collision dynamics to analyze clustering in active particles with explicit solvent effects.

Findings

Hydrodynamics significantly influence clustering mechanisms.

Growth modes vary with activity and hydrodynamic interactions.

Multi-particle collision dynamics effectively captures hydrodynamic effects in active matter.

Abstract

We study dynamics of clustering in systems containing active particles that are immersed in an explicit solvent. For this purpose we have adopted a hybrid simulation method, consisting of molecular dynamics and multi-particle collision dynamics. In our model, overlap-avoiding passive interaction of an active particle with another active particle or a solvent particle has been taken care of via variants of Lennard-Jones potential. Dynamic interaction among the active particles has been incorporated via the Vicsek-like self-propulsion that facilitates clustering. We quantify the effects of activity and importance of hydrodynamics on the dynamics of clustering via variations of relevant system parameters. We work with low overall density of active particles. For this the morphology consists of disconnected clusters, the mechanism of growth switching among particle diffusion, diffusive coalescence and ballistic aggregation, depending upon the presence or absence of active and hydrodynamic interactions. Corresponding growth laws have been quantified and discussed in the background of appropriate theoretical pictures. Our results suggest that multi-particle collision dynamics is an effective method for investigation of hydrodynamic phenomena even in active matter systems.