Novel morphologies for laterally decorated metaparticles: Molecular dynamics simulation

TL;DR

This study uses molecular dynamics simulations to discover two new morphologies of nano-sized metaparticles with lateral decorations, revealing their structures, order parameters, and reorientation mechanisms, which could influence their opto-mechanical properties.

Contribution

The paper introduces two novel morphologies of lateral decorated metaparticles and analyzes their structural and orientational properties through molecular dynamics simulations.

Findings

Discovery of $ extrm{uCol}_ extrm{h}$ and $ extrm{wCol}_ extrm{h}$ morphologies.

Identification of strong and weak liquid crystalline order in the new phases.

Insights into mesogen reorientation mechanisms for different attachment types.

Abstract

We consider a mesoscale model for nano-sized metaparticles (MPs) composed of a central sphere decorated by polymer chains with laterally attached spherocylinder. The latter mimics the mesogenic (e.g., cyanobiphenyl) group. Molecular dynamics simulations of $100$ MPs reveal the existence of two novel morphologies: $\textrm{uCol}_\mathrm{h}$ (hexagonal columnar arrangement of MPs with strong uniaxial order of mesogens collinear to the columns axis) and $\mathrm{wCol}_\mathrm{h}$ [the same arrangement of MPs but with weak or no liquid crystalline (LC) order]. Collinearity of the LC director and the columnar axis in $\textrm{uCol}_\mathrm{h}$ morphology indicates its potentially different opto-mechanical response to an external perturbation as compared to the columnar phase for the terminally attached mesogens. Preliminary analysis of the structures of both phases is performed by studying the order parameters and by visualisation of the MPs arrangements. Different mechanisms for the mesogens reorientation are pointed out for the cases of their terminal and lateral attachment.