Related Experiment Video
Updated: Apr 5, 2026
09:26
Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
10.6K
Particles with changeable topology in nematic colloids.
Miha Ravnik1, Simon Čopar, Slobodan Žumer
1Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia.
Summary
Nematic colloids with changing shapes alter topological defects. Toroidal particles form point defects, while knotted particles create complex links, offering insights into topological field effects.
Area of Science:
- Soft Matter Physics
- Materials Science
- Topology
Background:
- Nematic colloids are versatile systems for studying topological phenomena.
- Understanding how inclusions affect ordering fields is crucial in soft matter.
- Topological defects in liquid crystals exhibit complex behaviors.
Purpose of the Study:
- To investigate the impact of colloidal particle shape morphing on topological defect structures in nematic fields.
- To explore the relationship between particle topology (toroidal, knotted) and defect dynamics.
- To analyze the topological transformations of defects induced by particle shape changes.
Main Methods:
- Utilizing nematic colloids as a controllable platform.
- Inducing shape morphing in toroidal and knotted colloidal particles.
- Observing and analyzing changes in topological defect structures.
- Calculating and visualizing Pontryagin-Thom surfaces for detailed topological analysis.
Main Results:
- Colloidal particle morphing alters their Euler characteristic, significantly affecting the nematic field.
- Toroidal particles transition from loop defects to point defects.
- Knotted (trefoil) particles form complex, multi-component links with defect loops, which simplify upon tightening.
- Observed defect rewirings driven by particle shape transformations.
Conclusions:
- Nematic colloids provide a tunable system for exploring topological defect dynamics.
- Particle topology and shape morphing are key factors in dictating defect structures and transformations.
- This study reveals intricate defect rewiring cascades driven by colloidal shape changes.
Related Concept Videos
01:29The Colloidal State
152
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called...
152
03:22Colloids
22.1K
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...
22.1K
01:17Colloids and Suspensions
3.9K
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles visible to the naked eye or seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. The suspended particles in a suspension settle out after some time of mixing. The separation of particles from a suspension is...
3.9K
01:09Colloidal precipitates
6.8K
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
6.8K