Ex Libris: News from the Library
This week, the Library will host the final Lunchtime Lecture for this academic year. On Wednesday, May 2, Prof. Ömer Dağ of the Chemistry Department will deliver a talk entitled "The Fourth Phase of Matter: Liquid Crystals." Most people know about the three phases of matter -- solid, liquid and gas -- but you may be less familiar with the fourth phase, liquid crystals (LC). Discovered in 1888 by Friedrich R. Reinitzer and later named by Otto Lehmann, liquid crystals have impacted many areas of science and engineering, and by extension our daily lives: from liquid crystal displays (LCDs) used in watches and pocket calculators to advanced VGA computer screens, liquid crystal thermometers and optical imaging. The LC phase has also been used as a synthesis media for advanced materials in the field of nanotechnology. The liquid crystal phase is not a common property of matter, like the other phases, but can be observed in certain types of material. Some materials show the LC phase through heating (thermotropic) and some show it in the presence of a second matter, a solvent (lyotropic).
In his lecture, Prof. Dağ will discuss various applications of the LC phases in general and the use of lyotropic liquid crystalline (LLC) phases for designing solid materials with advanced functionality. His research focuses on a type of LLC phase that was discovered by his group at Bilkent University in 2001. This new LLC phase consists of a simple salt and surfactant that together self-assemble into the fourth phase of matter. The structures in this matter are unique and are impossible to replicate in other phases of matter employing other known methods and technologies. The Bilkent group works on the transformation of LLC materials into solid robust, stable, thermally resistive insulating, semi-conducting and metallic materials in the form of powders and thin films with excessive and extensive surface area. The materials generated using LLC phases may find applications in a very broad range of fields in science and engineering.
The lecture will take place in the Art Gallery, and will start at 12:40 p.m. on Wednesday. Lunchtime refreshments will be provided. We look forward to seeing you all there!