Development of fundamental theory of exciton and charge dynamics for efficient use of solar light

• Project/Area Number: 18H01937
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 32010:Fundamental physical chemistry-related
• Research Institution: The University of Tokyo
• Principal Investigator: Tamura Hiroyuki 東京大学, 先端科学技術研究センター, 特任准教授 (60390655)
• Co-Investigator(Kenkyū-buntansha): 石北 央 東京大学, 先端科学技術研究センター, 教授 (00508111) ; 石崎 章仁 分子科学研究所, 理論・計算分子科学研究領域, 教授 (60636207)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000); Fiscal Year 2020: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2019: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2018: ¥7,410,000 (Direct Cost: ¥5,700,000、Indirect Cost: ¥1,710,000)
• Keywords: 電子移動 / 励起エネルギー移動 / シングレット・フィッション / アップコンバージョン / 光合成 / 有機系太陽電池 / 励起子 / フォトンアップコンバージョン / 第一原理計算 / 量子ダイナミックス計算 / 太陽電池 / シングレットフィッション / 有機太陽電池 / 電荷分離

Outline of Final Research Achievements

In this study, we analyze the mechanisms of singlet fission, which generates two triplet excitons from a singlet exciton, and TTA, which is a reverse reaction of singlet fission, in molecular condensates by means of first principles calculations and quantum dynamics calculations. The effects of molecular packing on the reaction mechanisms are clarified. Besides, we clarify the reaction mechanisms of photon up-conversion in molecules adsorbed on lanthanide cluster via spin-orbit coupling and electron exchanges. Further, we analyze charge separation mechanisms in photosynthetic reaction centers using the same approach. We clarify the mechanism that leads to unidirectional charge separation in the reaction centers of photosystem II and purple bacteria.

Academic Significance and Societal Importance of the Research Achievements

太陽光エネルギーの効率利用のための基礎的知見を得るため、近年注目されているシングレット・フィッションとフォトン・アップコンバージョンの機構、および光合成系の電子・エネルギー移動に関する理論研究を行った。シングレット・フィッションは短波長光の量子効率の飛躍的増大につながり、フォトン・アップコンバージョンは通常の太陽電池や光触媒で利用できない長波長光の有効利用につながる。また、光合成系の基礎的知見は人口光合成系の設計指針につながる。

Research Products

• [Journal Article] Nature of Asymmetric Electron Transfer in the Symmetric Pathways of Photosystem I (2021)
  • Author(s): Mitsuhashi Koji、Tamura Hiroyuki、Saito Keisuke、Ishikita Hiroshi
  • Journal Title: The Journal of Physical Chemistry B Volume: 125 Issue: 11 Pages: 2879-2885
  • DOI: 10.1021/acs.jpcb.0c10885
  • Peer Reviewed / Open Access
• [Journal Article] Triplet Exciton Transfers and Triplet?Triplet Annihilation in Anthracene Derivatives via Direct versus Superexchange Pathways Governed by Molecular Packing (2020)
  • Author(s): Tamura Hiroyuki
  • Journal Title: The Journal of Physical Chemistry A Volume: 124 Issue: 39 Pages: 7943-7949
  • DOI: 10.1021/acs.jpca.0c06835
  • Peer Reviewed
• [Journal Article] Lanthanide-doped inorganic nanoparticles turn molecular triplet excitons bright (2020)
  • Author(s): Han Sanyang、Deng Renren、Gu Qifei、Ni Limeng、Huynh Uyen、Zhang Jiangbin、Yi Zhigao、Zhao Baodan、Tamura Hiroyuki、Pershin Anton、Xu Hui、Huang Zhiyuan、Ahmad Shahab、Abdi-Jalebi Mojtaba、Sadhanala Aditya、Tang Ming Lee、Bakulin Artem、Beljonne David、Liu Xiaogang、Rao Akshay
  • Journal Title: Nature Volume: 587 Issue: 7835 Pages: 594-599
  • DOI: 10.1038/s41586-020-2932-2
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Acquirement of water-splitting ability and alteration of the charge-separation mechanism in photosynthetic reaction centers (2020)
  • Author(s): Tamura Hiroyuki、Saito Keisuke、Ishikita Hiroshi
  • Journal Title: Proceedings of the National Academy of Sciences Volume: 117 Issue: 28 Pages: 16373-16382
  • DOI: 10.1073/pnas.2000895117
  • Peer Reviewed / Open Access
• [Journal Article] Long-Range Exciton Diffusion via Singlet Revival Mechanism (2019)
  • Author(s): Tamura Hiroyuki、Azumaya Koki、Ishikita Hiroshi
  • Journal Title: The Journal of Physical Chemistry Letters Volume: 10 Issue: 24 Pages: 7623-7628
  • DOI: 10.1021/acs.jpclett.9b03029
  • Peer Reviewed
• [Journal Article] Singlet exciton fission via an intermolecular charge transfer state in coevaporated pentacene-perfluoropentacene thin films (2019)
  • Author(s): Kim Vincent O.、Broch Katharina、Belova Valentina、Chen Y. S.、Gerlach Alexander、Schreiber Frank、Tamura Hiroyuki、Della Valle Raffaele Guido、D’Avino Gabriele、Salzmann Ingo、Beljonne David、Rao Akshay、Friend Richard
  • Journal Title: The Journal of Chemical Physics Volume: 151 Issue: 16 Pages: 164706-164706
  • DOI: 10.1063/1.5130400
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Mechanism of protonation of the over-reduced Mn4CaO5 cluster in photosystem II (2019)
  • Author(s): Saito Keisuke、Ishikita Hiroshi
  • Journal Title: Biochimica et Biophysica Acta (BBA) - Bioenergetics Volume: 1860 Issue: 10 Pages: 148059-148059
  • DOI: 10.1016/j.bbabio.2019.148059
  • Peer Reviewed / Open Access
• [Journal Article] Ultrafast carbon monoxide photolysis and heme spin-crossover in myoglobin via nonadiabatic quantum dynamics (2018)
  • Author(s): Falahati Konstantin、Tamura Hiroyuki、Burghardt Irene、Huix-Rotllant Miquel
  • Journal Title: Nature Communications Volume: 9 Issue: 1 Pages: 4502-4502
  • DOI: 10.1038/s41467-018-06615-1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Robust singlet fission in pentacene thin films with tuned charge transfer interactions (2018)
  • Author(s): K. Broch, J. Dieterle, F. Branchi, N.J. Hestand, Y. Olivier, H. Tamura, C. Cruz, V.M. Nichols, A. Hinderhofer, D. Beljonne, F.C. Spano, G. Cerullo, C.J. Bardeen, and F. Schreiber
  • Journal Title: Nature Communications Volume: 9 Issue: 1 Pages: 954-954
  • DOI: 10.1038/s41467-018-03300-1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Mechanism of Radical Formation in the H-Bond Network of D1-Asn298 in Photosystem II (2018)
  • Author(s): Kawashima Keisuke、Saito Keisuke、Ishikita Hiroshi
  • Journal Title: Biochemistry Volume: 57 Issue: 33 Pages: 4997-5004
  • DOI: 10.1021/acs.biochem.8b00574
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Energetic insights into two electron transfer pathways in light-driven energy-converting enzymes (2018)
  • Author(s): K. Kawashima, H. Ishikita
  • Journal Title: Chem. Sci. Volume: 9 Issue: 17 Pages: 4083-4092
  • DOI: 10.1039/c8sc00424b
  • Peer Reviewed / Open Access
• [Journal Article] Non-Markovian Quantum-Classical Ratchet for Ultrafast Long-Range Electron-Hole Separation in Condensed Phases (2018)
  • Author(s): Kato Akihito、Ishizaki Akihito
  • Journal Title: Physical Review Letters Volume: 121 Issue: 2 Pages: 026001-026001
  • DOI: 10.1103/physrevlett.121.026001
  • Peer Reviewed
• [Journal Article] Intramolecular Vibrations Complement the Robustness of Primary Charge Separation in a Dimer Model of the Photosystem II Reaction Center (2018)
  • Author(s): Fujihashi Yuta、Higashi Masahiro、Ishizaki Akihito
  • Journal Title: The Journal of Physical Chemistry Letters Volume: 9 Issue: 17 Pages: 4921-4929
  • DOI: 10.1021/acs.jpclett.8b02119
  • Peer Reviewed
• [Presentation] Combined Electronic Structure and Quantum Dynamical Analysis for Charge Separation and Singlet Fission (2018)
  • Author(s): 田村宏之
  • Organizer: Nonadiabatica 2018: Theory of nonadiabatic processes, Jerusalem, Israel
  • Int'l Joint Research / Invited