Toroidal nuclei of columnar lyotropic chromonic liquid crystals coexisting with isotropic phase

TL;DR

This paper investigates the unique toroidal shapes of nuclei in columnar lyotropic chromonic liquid crystals coexisting with isotropic phases, revealing how concentration and crowding agents influence their geometry through elasticity and interfacial tension.

Contribution

It provides the first experimental and theoretical analysis of toroidal nuclei in these liquid crystals, highlighting the role of molecular concentration and crowding agents in shape formation.

Findings

Toroidal nuclei shape depends on concentration and polyethylene glycol presence.

High concentrations produce thick toroids with small holes.

Low concentrations lead to thin toroids with large holes.

Abstract

Nuclei of ordered materials emerging from the isotropic state usually show a shape topologically equivalent to a sphere; the well-known examples are crystals and nematic liquid crystal droplets. In this work, we explore experimentally and theoretically the nuclei of columnar lyotropic chromonic liquid crystal coexisting with the isotropic phase that are toroidal in shape. The geometry of toroids depends strongly on the molecular concentrations and presence of a crowding agent, polyethylene glycol. High concentrations result in thick toroids with small central holes, while low concentrations yield thin toroids with wide holes. The multitude of the observed shapes is explained by the balance of bending elasticity and anisotropic interfacial tension.