1. 1.1 The World of Liquid Crystal Department of Chemistry Yonsei University Moon-Gun Choi

2. 1.2 Discovery of Liquid Crystals  The end of the 19th century Austrian botanist Friedrich Reinitzer  to study the role of cholesterol in plants

3. 1.3 Discovery of Liquid Crystals  Otto Lehmann, examined the cloudy ‘in-between phase’ “mesophase”

4. 1.4 Identifying a Liquid Crystal  Polarizing Optical Microscope  DSC(Differential Scanning Calorimeter)

5. 1.5 Why Liquid Crystals Form? Uneven distribution of electrons in the molecule  Intermolecular forces  Strong enough to cause the molecule line up in the same overall direction but not strong enough to hold them firmly in one place (over a certain range of temperatures)

6. 1.6 Why Liquid Crystals Form?  The Fourth State of Matter

7. 1.7 Types of Liquid Crystals

8. 1.8 Liquid Crystal Display Industry

9. 1.9 The Chemistry of Liquid Crystals  Understand which factors of the molecular structure give rise to LC behavior.  Tailor the molecules they made to give them the properties required for useful applications.  Align parallel to an electric field  Liquid crystal phase over a large temperature range  High chemical stability

10. 1.10 The Liquid Crystals that Revolutionized the Display Industry

11. 1.11 The Polymer Dispersed Liquid Crystal(PDLC) Display (SMART WINDOW)

12. 1.12 Discotic Liquid Crystal Materials and Molecular Wires

13. 1.13 Types of Columnar LC Phases

14. 1.14 Schematic Representation of Five Discotic Phases

15. 1.15 Various phases of calamatics and discotics molecules

16. 1.16 LC behavior depends upon the concentration in solution Lyotropic Liquid Crystal >

17. 1.17 LC behavior depends upon the temperature Thermotropic Liquid Crystal

18. 1.18 Properties of Metallomesogen  Various 3-D Structure  Ferroelectric Property  NLO Property  Paramagnetic Property by forming stable radical

19. 1.19 Publications on Metallomesogen

20. 1.20 Examples of Metallomesogen

21. 1.21 Examples of Metallomesogen Fe Bicontinuous cubic ( bcc ) Columnar Isotropic liquid Crystal Temperature( o C)

22. 1.22 Applications of Liquid Crystals

23. 1.23 Applications of LC Display Device

24. 1.24 Ferroelectric, Antiferroelectric LC  Ferroelectric  permanent dipole moment in the absence of an external electric filed.  Ferroelectricity of smectic C*  switch very quickly (μs vs ms)  Antiferroelectric  tilt direction alternates between layers

25. 1.25 Liquid Crystal Polymers

26. 1.26 Soaps and Detergents as an Example of LC

27. 1.27 Liquid Crystals in Nature

28. 1.28 Semi-flexible Main-Chain Polymer

29. 1.29 Side-Group LC Polymers for Optical Memories

30. 1.30 Liquid Crystals and Life

31. 1.31 Liquid Crystals and Life