Born October 3, 1920 in Shizuoka Prefecture, Japan.
Chairman, Kanagawa Academy of Science and Technology, Japan.
Prize of the Chemical Society of Japan (1966); Asahi Prize (1971); Japan Academy Prize (1978); Jawaharlal Nehru Birth Centenary Medal (1996); J. Heyrovsky Medal (1996): A Person of Cultural Merits (1985); An Order of Cultural Merits (1990); Member of Deutsche Akademie der Naturforscher Leopoldina (1983); Member of the Japan Academy (1984); Honorary Member of Chinese Chemical Society (1988); Foreign Fellow of Indian National Science Academy (1989); Honorary Member of the Royal Institution (London (1989); Foreign Member of the Royal Swedish Academy of Sciences (1990); Honorary D.Sc., University of Nebraska (1994); Honary Foreign Member of Korean Academy of Science and Technology (1995).
More than 300 papers on electronic structures and spectra of p-electron systems, molecular interactions (hydrogen bonding and electron donor-acceptor interaction), reaction intermediates and mechanisms, dynamic behaviour of excited molecules, and external magnetic field effects on chemical reactions.
Hydrogen Bonding Effect on Electronic Spectra: The effect was observed for phenol-ether systems separately from usual solvent effects. This finding opened the way for theoretical and experimental studies of hydrogen bonding with the aid of electronic spectra.
Intramolecular Electron-Transfer Interaction and Electronic Spectra: In electronic spectra of some substituted benzenes were found extra bands besides the shifted bands of benzene itself. These extra bands were demonstrated experimentally and theoretically to be due to intramolecular electron-transfer between the benzene ring and substitutent groups.
Electron Donor-Acceptor Interaction and its Application to Chemical Reactions: Electronic structures and spectra of electron donor-acceptor complexes were extensively studied and the existence of intermolecular charge-transfer triplet states was demonstrated. The charge-transfer theory of aromatic substitution and other organic reactions was proposed from consideration of relative heights of the HOMO and LUMO of component molecules.
Reaction Intermediates and Reaction Mechanism: Unstable reaction intermediates were detected by the aid of ns and ps time-resolved laser spectroscopy, charge-transfer intermediate states being actually observed for some reactions as expected from the charge-transfer theory.
External Magnetic Field Effects on Photochemical and Photophysical Phenomena: External magnetic field effects on reaction yields and rates were observed for various kinds of photochemical reactions in solution and were explained in term of the radical-pair model. External magnetic field effects were found for emission from excited singlet (nonmagnetic) states.