Positioning of Cubic Shaped Particles with Different Edge Structures in Nematic Medium

Download

10.18466-cbayarfbe.835483-1429610.pdf

Date

2021-01-01

Author

KARAUSTA, ASLI
Büküşoğlu, Emre

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

129
views

33
downloads

Liquid crystals (LC) are phases of matter that possess long range orientational order while maintaining fluidic properties. LCs have been shown to provide a medium that result in self-assembly of the colloidal particles through elastic interactions. One parameter that affects the positioning of the particles in LC medium is the edge sharpness of the particles. Simulation studies in the literature suggests that the edge sharpness of the particles directly affect the LC director profile at the vicinity of the particles, and playing a critical role in the formation and the shapes of the topological defects. This article presents a systematic study to show the effects of the edge sharpness on the orientation and the defect structure around the cubic shaped particles. The particles were shown to orient with their diagonal preferably parallel to the direction of the far field nematic director when the particles mediate planar anchoring. Whereas the particles with homeotropic anchoring did not exhibit strong preference in their orientation. We also showed defect structures to form around the particles with homeotropic surface anchoring. The defect structure around the particles with round edges were ring shaped, whereas the defects with Sshapes were formed around sharp-edged or truncated particles. The findings herein were found to be consistent with the simulations present in literature. The findings would find use in next generation materials for optics, photonics and responsive systems.

Subject Keywords

Alignment, Colloids, Defects, Liquid Crystals

URI

http://dx.doi.org/10.18466/cbayarfbe.835483
https://hdl.handle.net/11511/96513

Journal

Celal Bayar Üniversitesi Fen Bilimleri Dergisi

DOI

https://doi.org/10.18466/cbayarfbe.835483

Collections

Department of Chemical Engineering, Article

Suggestions

OpenMETU
Core

Design of functional materials using liquid crystals as molecular templates Karausta, Aslı; Büküşoğlu, Emre; Kalıpçılar, Halil; Department of Chemical Engineering (2018) Liquid crystal (LC) is a phase of material which is intermediate to a crystalline solid and an isotropic liquid such that the molecules flow but retain a degree of long-range orientational ordering. LCs, due to their long range orientational ordering and fluidic properties, can be used in templated synthesis of polymeric materials as well as self assembly of the microparticles incorporated into the LCs. In the first part of this thesis, we sought to provide control over alignment of the polymer chains, alig...
Identification and sorting of particle chirality using liquid crystallinity AKDENİZ, BURAK; Batır, Özge; Büküşoğlu, Emre (Elsevier BV, 2020-08-15) Particles dispersed in liquid crystals (LCs) have been shown to assemble due to the elastic interactions arising from the molecular anisotropy. Studies have shown that the alignment of the particles within LCs were strongly dependent on the surface director of LCs on particles. Different from the past studies involving particles with degenerate planar anchoring of LCs, this study shows that the azimuthal surface director can be used to control and finely tune the positioning of the particles in LCs. Specifi...
Controlled synthesis of organic-inorganic composite particles Erçelik, Elif; Büküşoğlu, Emre; Aydoğan, Nihal; Department of Chemical Engineering (2022-8-26) Liquid crystal (LC) is a state of matter having long-range orientational order between crystalline solid and isotropic liquid, and its molecular orientation can be altered with external stimuli. The polymerization of liquid crystal droplets has been widely used for the synthesis of LC-templated functional materials due to its ordering property and fluidic behavior. In this study, we investigated the synthesis of composite particles with controlled internal and interfacial structure using surface-modified na...
Liquid crystal-templated synthesis of polymeric microparticles with complex nanostructures Akdeniz, Burak; Büküşoğlu, Emre; Department of Chemical Engineering (2019) Liquid crystals (LC), when combined with photolithography, enable synthesis of microparticles with two- and three-dimensional shapes and internal complexities. We prepared films of nematic LCs using mixtures of reactive (RM257) and non-reactive mesogens (E7) with controlled alignment of LCs at the confining surfaces, photopolymerized the RM257 using a photomask, and then extracted the unreacted mesogens to yield polymeric microparticles. The extraction resulted in a controlled anisotropic shrinkage with an ...
Characterization of defect states in Ag0.5Cu0.5In5S8 solid solution by photoluminescence and thermally stimulated current Hasanlı, Nızamı (2015-08-01) Photoluminescence (PL) and thermally stimulated current (TSC) in Ag(0.5)Cu(0.5)in(5)S(8) solid solution grown by Bridgman method have been studied in the photon energy region of 1.46-1.60 eV and in the temperature range of 10-42 K (PL) and in the temperature range of 10-100 K with heating rate of 1.01 K/s (TSC). A PL band centered at 1.53 eV was observed at T = 10 K. Variations of emission band has been studied as a function of excitation laser intensity in the 1.8-183.0 mW cm(-2) range. Radiative transitio...

Citation Formats

A. KARAUSTA and E. Büküşoğlu, “Positioning of Cubic Shaped Particles with Different Edge Structures in Nematic Medium,” Celal Bayar Üniversitesi Fen Bilimleri Dergisi, vol. 17, no. 2, pp. 115–120, 2021, Accessed: 00, 2022. [Online]. Available: http://dx.doi.org/10.18466/cbayarfbe.835483.