Liquid Crystals by Volodymyr Levchuk Anton Kravchuk Yuliia Barannyk

WHAT ARE THE LIQUID CRYSTALS? This is the phase state into which certain substances pass under certain conditions (temperature, pressure, concentration in solution). Liquid crystals simultaneously have both of the properties of liquids (fluidity) and crystals (anisotropy).

LIQUID CRYSTAL GROUPS Liquid crystals can be divided into thermotropic, lyotropic and metallotropic groups. Thermotropic Lyotropic Metallotropic Liquid Crystals

THERMOTROPIC LCs PHASES Nematic phase is one of the most common LC phases. Nematics have the optical properties of uniaxial crystals and this makes them extremely useful in liquid-crystal displays. Alignment in a nematic phase Schematic of alignment in the smectic phases. The smectic phases The smectic A phase (left) has molecules organized into layers. In the smectic C phase (right), the molecules are tilted inside the layers. Schematic of ordering in chiral liquid crystal phases. Chiral phases The chiral nematic phase (left), also called the cholesteric phase, and the smectic C* phase (right).

THE LIQUID CRYSTALS AND NATURE Liquid crystals are also fundamentally important to life. DNA and cell membranes have liquid crystal phases. Our brains are around 70% liquid crystal, and liquid crystals are also found in muscles, the amazing iridescent colors of some insects, and also slug slime!

APPLICATIONS OF THE LIQUID CRYSTALS One of the important directions in the use of liquid crystals is thermography In medicine the liquid crystal indicator on the patient's skin quickly diagnoses latent inflammation and even swelling. Kevlar, the most widely used body armor is made up of intertwined liquid crystal polymers.

APPLICATIONS OF THE LIQUID CRYSTALS Indicators familiar to everyone on the electronic clock Color TV with a liquid crystal screen Liquid crystal display for microcontrollers

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