Self-assembly of anisotropic particles on curved surfaces

TL;DR

This study uses molecular dynamics simulations to explore how surface curvature influences the self-assembly of anisotropic particles, revealing new ordered structures and phase behaviors driven by curvature effects.

Contribution

It uncovers the coupling between particle anisotropy and surface curvature, demonstrating how curvature induces novel structures and alters the free energy landscape of assemblies.

Findings

Curvature induces unique ordered structures absent on flat surfaces.

Surface curvature leads to microdomain formation and mesoscale ordering.

High curvature can cause a glass-like dynamical state.

Abstract

The surface curvature of membranes, interfaces, and substrates plays a crucial role in shaping the self-assembly of particles adsorbed on these surfaces. However, little is known about the interplay between particle anisotropy and surface curvature and how they couple to alter the free energy landscape of particle assemblies. Using molecular dynamics simulations, we investigate the effect of prescribed curvatures on a quasi-2D assembly of anisotropic patchy particles. By varying curvature and surface coverage, we uncover a rich geometric phase diagram, with curvature inducing ordered structures entirely absent on planar surfaces. Large spatial domains of ordered structures can contain hidden microdomains of orientational textures imprinted by the surface on the assembly. The dynamical landscape is also reshaped by surface curvature, with a glass-like state emerging at modest densities and high curvature. Changes to the symmetry of the surface curvature are found to result in distinct structures, including phases with mesoscale ordering. Our findings show that the coupling between surface curvature and particle geometry opens an unexplored space of morphologies and structures that can be exploited for material design.