Pritzker School of Molecular Engineering; University of Chicago; Chicago; USA; Cornell University
División de Ciencias e Ingenierías; Campus León; Universidad de Guanajuato; León (Gto.) 37150; Mexico
Departamento de Materiales y Minerales; Universidad Nacional de Colombia-Sede Medellín; Medellín; Colombia; Facultad de Ciencias Básicas, Sociales y Humanas
Department of Chemical and Biomolecular Engineering; Cornell University; Ithaca; USA
Pritzker School of Molecular Engineering; University of Chicago; Chicago; USA; Departamento de Materiales y Minerales
Pritzker School of Molecular Engineering; University of Chicago; Chicago; USA; Materials Science Division
Cuboidal liquid crystal phases – the so-called blue phases – consist of a network of topological defects arranged into a cubic symmetry. They exhibit striking optical properties, including Bragg reflection in the visible range and fast response times. Confining surfaces can interfere with the packing of such a network, leading to structures that have not been explored before. In this work, a Landau–de Gennes free energy formalism for the tensor alignment field Q is used to investigate the behavior of chiral liquid crystals under non-isotropic confinement. The underlying free energy functional is solved by relying on a Monte Carlo method that facilitates efficient exploration of configuration space. The results of simulations are expressed in terms of phase diagrams as a function of chirality and temperature for three families of spheroids: oblate, spherical, and prolate. Upon deformation, blue phases adapt and transform to accommodate the geometrical constraints, thereby resulting in a wider range of thermal stability. For oblate spheroids, confinement interferes with the development of a full blue phase structure, resulting on a combination of half skyrmions. For prolate spheroids, the blue phases are hybridized and exhibit features of blue phases I and II. More generally, it is shown that mechanical deformation provides an effective means to control, manipulate and stabilize blue phases and cholesterics confined in tactoids.
Palacio-Betancur, Viviana, Armas-Pérez, Julio C., Villada-Gil, Stiven, Abbott, Nicholas L., Hernández-Ortiz, Juan P., & de Pablo, Juan J. (2020). Cuboidal liquid crystal phases under multiaxial geometrical frustration. Soft Matter, 16(4). https://doi.org/10.1039/c9sm02021g
@article{osti_1603448,
author = {Palacio-Betancur, Viviana and Armas-Pérez, Julio C. and Villada-Gil, Stiven and Abbott, Nicholas L. and Hernández-Ortiz, Juan P. and de Pablo, Juan J.},
title = {Cuboidal liquid crystal phases under multiaxial geometrical frustration},
annote = {Cuboidal liquid crystal phases – the so-called blue phases – consist of a network of topological defects arranged into a cubic symmetry. They exhibit striking optical properties, including Bragg reflection in the visible range and fast response times. Confining surfaces can interfere with the packing of such a network, leading to structures that have not been explored before. In this work, a Landau–de Gennes free energy formalism for the tensor alignment field Q is used to investigate the behavior of chiral liquid crystals under non-isotropic confinement. The underlying free energy functional is solved by relying on a Monte Carlo method that facilitates efficient exploration of configuration space. The results of simulations are expressed in terms of phase diagrams as a function of chirality and temperature for three families of spheroids: oblate, spherical, and prolate. Upon deformation, blue phases adapt and transform to accommodate the geometrical constraints, thereby resulting in a wider range of thermal stability. For oblate spheroids, confinement interferes with the development of a full blue phase structure, resulting on a combination of half skyrmions. For prolate spheroids, the blue phases are hybridized and exhibit features of blue phases I and II. More generally, it is shown that mechanical deformation provides an effective means to control, manipulate and stabilize blue phases and cholesterics confined in tactoids.},
doi = {10.1039/c9sm02021g},
url = {https://www.osti.gov/biblio/1603448},
journal = {Soft Matter},
issn = {ISSN 1744-683X},
number = {4},
volume = {16},
place = {United States},
publisher = {Royal Society of Chemistry},
year = {2020},
month = {01}}
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 371, Issue 1988https://doi.org/10.1098/rsta.2012.0266
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 376, Issue 2112https://doi.org/10.1098/rsta.2017.0042