A continuum theory is used to study the effects of homeotropic nano-particles on degenerate planar liquid crystal interfaces. Particle self-assembly mechanisms are obtained from careful examination of particle configurations on a planar film and on a spherical droplet. The free energy functional that describes the system is minimized according to Ginzburg–Landau and stochastic relaxations. The interplay between elastic and surface distortions and the desire to minimize defect volumes (boojums and half-Saturn rings) is shown to be responsible for the formation of intriguing ordered structures. As a general trend, the particles prefer to localize at defects to minimize the overall free energy. However, multiple metastable configurations corresponding to local minima can be easily observed due to the high energy barriers that separate distinct particle arrangements. Finally, we show that by controlling anchoring strength and temperature one can direct liquid-crystal mediated nanoparticle self-assembly along well defined pathways.
Londoño-Hurtado, Alejandro, Armas-Pérez, Julio C., Hernández-Ortiz, Juan P., & de Pablo, Juan J. (2015). Homeotropic nano-particle assembly on degenerate planar nematic interfaces: films and droplets. Soft Matter, 11(25). https://doi.org/10.1039/C5SM00940E
Londoño-Hurtado, Alejandro, Armas-Pérez, Julio C., Hernández-Ortiz, Juan P., et al., "Homeotropic nano-particle assembly on degenerate planar nematic interfaces: films and droplets," Soft Matter 11, no. 25 (2015), https://doi.org/10.1039/C5SM00940E
@article{osti_1603434,
author = {Londoño-Hurtado, Alejandro and Armas-Pérez, Julio C. and Hernández-Ortiz, Juan P. and de Pablo, Juan J.},
title = {Homeotropic nano-particle assembly on degenerate planar nematic interfaces: films and droplets},
annote = {A continuum theory is used to study the effects of homeotropic nano-particles on degenerate planar liquid crystal interfaces. Particle self-assembly mechanisms are obtained from careful examination of particle configurations on a planar film and on a spherical droplet. The free energy functional that describes the system is minimized according to Ginzburg–Landau and stochastic relaxations. The interplay between elastic and surface distortions and the desire to minimize defect volumes (boojums and half-Saturn rings) is shown to be responsible for the formation of intriguing ordered structures. As a general trend, the particles prefer to localize at defects to minimize the overall free energy. However, multiple metastable configurations corresponding to local minima can be easily observed due to the high energy barriers that separate distinct particle arrangements. Finally, we show that by controlling anchoring strength and temperature one can direct liquid-crystal mediated nanoparticle self-assembly along well defined pathways.},
doi = {10.1039/C5SM00940E},
url = {https://www.osti.gov/biblio/1603434},
journal = {Soft Matter},
issn = {ISSN 1744-683X},
number = {25},
volume = {11},
place = {United States},
publisher = {Royal Society of Chemistry},
year = {2015},
month = {05}}
Univ. of Wisconsin, Madison, WI (United States); Univ. of Chicago, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); Consejo Nacional de Ciencia y Tecnología in Mexico (CONACyT); Universidad Nacional de Colombia
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol. 221, Issue 1https://doi.org/10.1080/10587259208037516