Pi conjugated system bricolage (figuration) toward functional organic molecular systems

First of all, I would like to express my sincere thanks to Professor Ben Zhong Tang, the Editor-in-Chief of Materials Chemistry Frontiers, for his kind invitation to this themed issue, which collects studies made in the framework of the “π-System Figuration” project supported by Grant-in-Aid for Scientific Research on Innovative Areas, MEXT, Japan.

π-Electronic molecules and polymers that display electronic, optical, and magnetic functions have played a major role not only in fundamental chemistry but also in diverse research areas from materials to life sciences. A recent innovation of organic electronics stems from the studies on π-electronic materials, originating from the discovery of organic semiconductors in the 1950s. After that, through intensive studies including the discovery of conducting polymers, the first organic device was developed in the 1980s. More than 30 years after that, we believe that now is the time for the science of π-electronic systems to advance to the next stage.

One may realize that the π-electronic molecules which resulted in historic breakthroughs are always structurally simple and beautiful. With this fact in mind, we have designed new π-electronic molecules and assemblies that hold “beautility” based on the concept of “π-System Figuration”; although the term “figuration” may be unusual in chemistry and rather found in the fields of art and architecture, we intentionally used this term so as to represent our notion that “beautiful things are powerful and powerful things are beautiful”. We aim to develop superb π-electronic materials and functions, as well as to uncover new phenomena related to π-systems, through the control of the electronic and assembly structures of molecules.

This themed issue covers cutting-edge research, which focuses on (1) the development of new molecular frameworks based on state-of-the-art synthetic methodology, (2) the development of functional molecular and polymer assemblies, and (3) the development of analytical and theoretical methods that predict, design, and unveil the properties of the new π-electronic materials by utilizing state-of-the-art computational, measurement, and device techniques. As seen in several contributions, the dynamic motion and mechanical stimulus generated in π-electronic materials can largely perturb the electronic function of the materials. We consider that harmonizing π-electronic functions with molecular motions is an important viewpoint for further pursuing new phenomena and functions.

Finally I would like to express thanks to all of the authors who accepted my invitations and contributed to this themed issue. I also thank Associate Editor Professor Shu Seki for his effort in launching the issue, and Dr Wenjun Liu as the Executive Editor of the journal, as well as all of the staff at Materials Chemistry Frontiers for their efforts dedicated to this themed issue.

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