Scaling laws for single-file diffusion of adhesive particles

TL;DR

This paper develops a scaling theory for single-file diffusion of adhesive particles, revealing how adhesion-induced clustering affects diffusion behavior over time and impacts molecular translocation in narrow pores.

Contribution

It introduces a novel scaling theory that describes the diffusive behavior of adhesive particles in single-file systems, accounting for clustering effects.

Findings

Adhesive interactions slow short-time diffusion due to clustering.

Adhesion enhances long-time subdiffusion, affecting overall transport.

The theory applies regardless of particle injection methods.

Abstract

Single-file diffusion refers to the Brownian motion in narrow channels where particles cannot pass each other. In such processes, the diffusion of a tagged particle is typically normal at short times and becomes subdiffusive at long times. For hard-sphere interparticle interaction, the time-dependent mean squared displacement of a tracer is well understood. Here we develop a scaling theory for adhesive particles. It provides a full description of the time-dependent diffusive behavior with a scaling function that depends on an effective strength of adhesive interaction. Particle clustering induced by the adhesive interaction slows down the diffusion at short times, while it enhances subdiffusion at long times. The enhancement effect can be quantified in measurements irrespective of how tagged particles are injected into the system. Combined effects of pore structure and particle adhesiveness should speed up translocation of molecules through narrow pores.