Experimental investigations on biaxial nematic and orthogonal biaxial smectic liquid crystals

Abstract

The quest for thermotropic biaxial nematic phase began forty years ago, when it was recognised that the molecules forming liquid crystal phases deviate from their presumed cylindrical shape. In recent years, the interest in the biaxial nematic phase formed by low molecular weight materials has significantly increased mainly due to its potential for device applications, providing a way to much faster switching than is possible with the presently used displays based on uniaxial nematic. The objectives of my PhD work are to -identify the phase biaxiality in nematic and orthogonal smectic phases -characterise and study the physical properties of nematic and orthogonal smectic phases by electro-optics, dielectric and infrared spectroscopy. The studies mainly include bent-core and bimesogens/dimers systems.