1. Introduction1.1 General Introduction1.2 Discovery of Diarylethene Molecular Photoswitches2. Reaction Mechanism2.1 Basic Concepts2.2 Theoretical Study2.3 Reaction Dynamics2.3.1 Cyclization Reaction2.3.2 Cycloreversion Reaction3. Photoswitching Performance3.1 Quantum Yield3.1.1 Photocyclization Quantum Yield3.1.2 Solvent Effect on Cyclization Quantum Yield3.1.3 Photocycloreversion Quantum Yield3.2 Thermal Stability3.3 Fatigue Resistance3.4 Fluorescence Property3.4.1 Turn-off Mode Photoswitching3.4.2 Turn-on Mode Photoswitching3.5 Chiral Property4. Photoswitchable Crystals4.1 Dichroism4.2 X-Ray Crystallographic Analysis4.3 Quantum Yield4.4 Multicoloured Systems and Nano-layered Periodic Structures4.5 Fluorescent Crystals4.6 Photomechanical Response4.6.1 Surface Morphology Change4.6.2 Reversible Shape Change4.6.3 Bending Response of Mixed Crystals5. Memory5.1 Single-Molecule Memory5.2 Near-Field Optical Memory5.3 Three-Dimensional Optical Memory5.4 Readout using Infrared (IR) Absorption, Raman Scattering and Refractive Index Changes6. Switches6.1 Single-Molecule Conductance Photoswitch6.2 Optical Switch based on Refractive Index Change6.3 Magnetism7. Surface Properties7.1 Surface Wettability7.2 Selective Metal Deposition7.3 Subwavelength Nanopatterning8. Polymers and Liquid Crystals8.1 Polymers8.2 Liquid Crystals9. Applications9.1 Organic Field-Effect Transistors (OFETs)9.2 Metal Organic Frameworks (MOFs)9.3 Super-resolution Fluorescence Microscopy9.3.1 Control of Cycloreversion Quantum Yield9.3.2 Fatigue Resistance9.3.3 Photoswitching with Single-Wavelength Visible Light9.3.4 Super-resolution Bioimaging9.4 Chemical Reactivity Control9.5 Biological Activity9.6 Colour Dosimeters10. Appendix
Masahiro Irie is an emeritus professor of Kyushu University. He received his B.S. and M.S. from Kyoto University and his Ph.D. in radiation chemistry from Osaka University. In 1968 he joined the Faculty of Engineering, Hokkaido University, as a research associate and started his research in photochemistry. He was the faculty members of at Osaka University, Kyushu University and Rikkyo University. He has been conducting research on molecular photoswitch systems for more than 40 years. In the middle of the 1980s he discovered thermally irreversible and fatigue resistant photochromic diarylethenes. Prof. Irie has authored over 500 scientific publications and has received numerous scientific awards, including Porter Medal (European Photochemistry Association, The Inter-American Photochemistry Society and Asian and oseanian Photochemsitry association), Theodor-Foerster-Preis (GDCh and Deutsche Bunsen-Gesellschaft, Germany) and The Chemical Society of Japan Award.