D
Daisuke Kosumi
Researcher at Kumamoto University
Publications - 70
Citations - 1061
Daisuke Kosumi is an academic researcher from Kumamoto University. The author has contributed to research in topics: Excited state & Bacteriochlorophyll. The author has an hindex of 19, co-authored 66 publications receiving 915 citations. Previous affiliations of Daisuke Kosumi include Osaka City University & Tohoku University.
Papers
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Journal ArticleDOI
Ultrafast Dynamics of All-trans-β-Carotene Explored by Resonant and Nonresonant Photoexcitations
TL;DR: The long-debated S(2)-S(1) relaxation in beta-carotene can be explained by a two-state model (S(2), S(1)) without involving any intermediate states.
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The dependence of the ultrafast relaxation kinetics of the S2 and S1 states in β-carotene homologs and lycopene on conjugation length studied by femtosecond time-resolved absorption and Kerr-gate fluorescence spectroscopies
Daisuke Kosumi,Masazumi Fujiwara,Ritsuko Fujii,Richard J. Cogdell,Hideki Hashimoto,Masayuki Yoshizawa +5 more
TL;DR: A model based on conical intersections between the potential energy curves of these excited singlet states can readily explain the measured relationships between the decay rates and the energy gaps.
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One- and two-photon pump–probe optical spectroscopic measurements reveal the S1 and intramolecular charge transfer states are distinct in fucoxanthin
Daisuke Kosumi,Toshiyuki Kusumoto,Ritsuko Fujii,Mitsuru Sugisaki,Yoshiro Iinuma,Naohiro Oka,Yuki Takaesu,Tomonori Taira,Masahiko Iha,Harry A. Frank,Hideki Hashimoto +10 more
TL;DR: In this article, the ultrafast relaxation kinetics of fucoxanthin in polar and non-polar solvents have been studied by femtosecond dispersed one-and two-photon pump-probe spectroscopies.
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Conjugation length dependence of relaxation kinetics in β-carotene homologs probed by femtosecond Kerr-gate fluorescence spectroscopy
TL;DR: In this paper, the lifetime of the S 2 (1 1 B u + ) state in all trans-carotenoids with a number of conjugated double bonds was investigated by femtosecond Kerr-gate fluorescence spectroscopy.
Journal ArticleDOI
Excited-state dynamics of pentacene derivatives with stable radical substituents.
Akitaka Ito,Akihiro Shimizu,Noriaki Kishida,Yusuke Kawanaka,Daisuke Kosumi,Hideki Hashimoto,Yoshio Teki +6 more
TL;DR: The excited-state dynamics of pentacene derivatives with stable radical substituents were evaluated in detail and showed ultrafast formation of triplet excited state(s) in the pentacenes moiety from a photoexcited singlet state through the contributions of enhanced intersystem crossing and singlet fission.