U.S.-Hungary Materials Research: Liquid Crystalline Mesophases of Bent Core Molecules

Kent State University, Kent OH

Investigators

Abstract

This US-Hungarian research project headed by Peter Palffy-Muhoray of Kent State University and Agnes Burka of the Hungarian Institute for Solid State Physics and Optics Budapest examines a new class of liquid crystals consisting of bent-shaped molecules. These ester type bent core liquid crystals range from low molecular weight materials to elastomers. The collaborative research plan involves synthesis, characterization, and modeling of such bent-core, or banana-shaped, molecules. Junior researchers from Kent State University are part of the distinguished US-Hungarian team. To determine the mesophases and physical properties of bent-core liquid crystals, the research partners will employ three experimental techniques: 1)Mechanical studies of thin films including linear electro-mechanical and rheological measurements of banana liquid crystal systems, where the overall chirality is set by surface interactions. 2)Electrical measurements which include determination of the polarization and dielectric spectroscopy. 3)Optical observations consisting of polarizing and confocal microscopy as well as electro-optic measurements and laser spectroscopy. The goal is to resolve a number of fundamental questions concerning the correlation between material parameters and pattern forming instabilities. For example, the researchers hope to explain observed achiral symmetry-breaking mechanisms and to understand how the structures form helical filaments in an isotropic melt. If successful, their results may help identify novel synthetic materials with optical and pyroelectric properties that have practical applications in information technology and biotechnology. This research project in experimental condensed matter physics fulfills the program objective of advancing scientific knowledge by enabling experts in the United States and Central Europe to combine complementary talents and share research resources in areas of strong mutual interest and competence.