Considerable interest has been focused on organic photochromic materials that change their color upon irradiation with light; the photogenerated species can be reversed to the initial species either by thermally or by subsequent irradiation with a specific wavelength of light. In particular, thermally reversible photochromic molecules offer the opportunity to change and reset the molecular properties by simply turning a light source on and off. In this project, we design and create high-performance fast photochromic materials which could eventually evolve into solid-state photonic materials with unique photoresponsive characters.

The present project elucidates radical-nano interfaces between open-shell compounds and electrodes. Using effective charge separation at these interfaces, we develop highly-efficient, ultrafast optoelectronic conversion. We also apply the radical-nano interfaces to solid-state electrochemistry, aiming at high energy-density, molecule-based rechargeable batteries.

To realize new functional magnetic materials and to develop innovative magnetic devices, this project, which is based on magnetochemistry, investigates the bottom-up synthesis of functional nanomaterials. Specifically, we will demonstrate next-generation high-density memories and electromagnetic wave absorbers using metal oxide-based nanomagnets. Moreover, to discover new phenomena due to the coupling effect between magnetism and ion conductivity (and/or photon), we will prepare a novel type of metal complex-based magnet by controlling the crystal structure and its dimensionalities. Through such investigations, we will elucidate the relationship between magnetic properties and molecular structure (or nanostructure).

We aim at creating a new class of functional π materials as key components for future electronics with high efficiency in the energy conversion and low energy consumption. Our approach is based on the development of sophisticated 2D-expanded π-conjugated skeletons and their clustering. We will tackle this subject by rational molecular designs based on quantum chemical calculations and competent synthesis including the development of our original reactions. Through the construction of flexible nanostructures with unusual photo- and electronic properties, dynamic functions, high-performance amorphous phase, or fluid condensed phase, we will establish the design principle for this class of soft materials.

Synthesis of hoop-shaped π-conjugated molecules as exemplified in cycloparaphenylenes, which possess simplest structural unit of arm-chair carbon nanotube, will be investigated through the supramolecular chemical approach. Applications of these molecules to organoelectronic device materials and elucidation of their functions by forming higher-order structures will be also studied. We will develop the science and technology of hoop-shaped π-conjugated molecules through this study.