• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

FT-ESR Study of Initial Process of Phtochemical Reactions

Research Project

Project/Area Number 08044071
Research Category

Grant-in-Aid for international Scientific Research

Allocation TypeSingle-year Grants
SectionJoint Research
Research InstitutionKYOTO UNIVERSITY

Principal Investigator

HIROTA Noboru  Kyoto Univ. Graduate School of Science, Professor, 大学院・理学研究科, 教授 (90093301)

Co-Investigator(Kenkyū-buntansha) NAKAGAWA Kouichi  Fukushima Prefectural Medical College, Assistant, 医学部, 助手 (00244393)
TERAZIMA Masahide  Kyoto Univ. Graduate School of Science, Associate Professor, 大学院・理学研究科, 助教授 (00188674)
WILLIGEN Hans von  Univ. of Massachusetts of Boston, Professor, ボストン校・化学科, 教授
OHARA Keishi  Ehime Univ. Faculty of Science, Assistant, 理学部, 助手 (10284390)
WILLIGEN Han  マサチューセッツ大学, 化学科(ボストン校), 教授
Project Period (FY) 1996
Project Status Completed (Fiscal Year 1996)
Budget Amount *help
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 1996: ¥2,700,000 (Direct Cost: ¥2,700,000)
KeywordsTime-Resolved EPR / CIDEP / xanthone / FT-EPR / Photochemical initial process / Phenotiazine
Research Abstract

At the international symposium on spin and magnetic field effects held in Novosibirsk in August, 1996 Hirota, van Willigen and Ohara discussed the detailed plan of the cooperative work. It was decided that the initial processes of photochemical reactions of xanthone of which a number of unsolved problems exist should be studied by FT-EPR method. Following this discussion, Ohara went to Boston in September to make FT-EPR measurements. In this work he obtained the following results.
1) Emissive polarization found in xanthone/2-propanol is mainly determined by the hydrogen abstraction of xanthone and its mechanism is radical pair mechanism (RPM).
2) The rise of the absorptive polarization observed in xanthone/2-propanol +HィイD22ィエD2O +HCl is very rapid determined by the time -resolution of the spectrometer and the mechanism is likely to be triplet mechanism (TM). However, the intensity of the polarization is very weak.
In November, Hirota made further measurement in Boston and examined the effect of the concentration of HCl on the polarization. It was found that inversion of the polarization of the hydroxypropyl radical from E to A takes place at a relatively low concentration of HCl. Moreover, it was found that the polarization of the xanthone ketyl radical showed an inversion from A to E. It was though that additional transient absorption experiments are needed to clarify the initial processes in the photochemistry of xanthone and work along this line was tried in Kyoto with Prof. van Willigen. However, this work has not been completed yet, and further work will be continued.
In addition to the above work Nakagawa made FT-EPR work on the hydrated electron in the SDS micelle produced by the photoionization of phenothiazine and its derivatives. He obtained detailed information about the phase of the CIDEP signal of the hydrated electron, dynamics of disappearance and quenching of the CIDEP signal of the hydrated electron.

Report

(2 results)
  • 1996 Annual Research Report   Final Research Report Summary
  • Research Products

    (15 results)

All Other

All Publications (15 results)

  • [Publications] K. Ohara, N. Hirota C. A. Stelen, H. van Willigen: "CW and FT-tme-resolued EPR Investigation of the Quenching Reaction of the 2-Hydroxpropan-2-ye Radical"Journal of physical chemistry. 100. 3070-3074 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K. Ohara, N. Hirota: "An Analysis of CIDEP mechanisms in the Hydrogen Abstraction Reactions of Excited Quenoxaline and Related Compounds"Bull. Chem. Soc., gapan. 69. 1517-1526 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K. Ohara, Y. Miura M. Terazima, N. Hirota: "CIDEP Studies in Low Froquency Microwave Regions : Magnetic Field Dependence of CIDEP of Spis -Correlated Radicals"Journal of physical chemistry. 101. 605-611 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Y. Kimura, D. Kanda M. Terazima, N. Hirota: "Solvent density Dependence of Translational Diffusion of Transient Radicals in the Medium Density Region of Tsifluoromethane"Journal of physical chemistry. 101(予定). (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 広田 襄: "分子磁性,新しい磁性体と反応制御(伊藤公一編)"学会出版センター. 23 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K. Ohara, N. Hirota, C. A. Steren, H. van Willigen: "CW and Time-resolved EPR investigation of the Quenching Reaction of 2-Hydroxypropan-2-yl Radical in 2-propanol"J. Phys. Chem. 100. 3070-3074 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K. Ohara, N. Hirota: "An Analysis of CIDEP Mechanisms in the Hydrogen Abstraction Reactions of Excited Quinoxaline and Related molecules"Bull. Chem. Soc., Jpn. 69. 1517-1526 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K. Ohara, Y. Miura, M. Terazima, N. Hirota: "Cidep Studies in Low Frequency Microwave Regions : Magnetic Field Dependence of CIDEP of Spin-Correlated Radical Pairs"J. Phys. Chem. 101. 605-611 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Y. Kimura, D. Kanda, M. Terazima, N. Hirota: "Solvent Density Dependence of Translational Diffusion of Trasient Radicals in Medium Density Regions of Trfluoromethane"J. Phys. Chem. 101 (in press).

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] N. Hirota: "Molecular Magnetism : New Magnetic Material and Reaction Control, K. Ttoh Ed."Gakkai Syppan Center. 373-396 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K.Ohara,N.Hirota C.A.Steren,Hvan Willigen: "CW and FT Time-resolved EPR Investigation of the Quenching Reaction of the 2-Hydroxy propan-2-yl Radical" Journal of Physical Chemistry. 100. 3070-3074 (1996)

    • Related Report
      1996 Annual Research Report
  • [Publications] K.Ohara,N.Hirota: "An Analysis of CIDEP Mechanisms in the Hydrogen Abstraction Reactions of Excited Quenoxaline and Related Compounds" Bull.Chem.Soc.Jpn.69. 1517-1526 (1996)

    • Related Report
      1996 Annual Research Report
  • [Publications] K.Ohara,Y.Miura M.Terazima,N.Hirota: "CIDEP Studies in Low-Frequency Microwave Regions:Magnetic Field Dependence of CIDEP of spin-correlated Radicals" Journal of Physical Chemistry. 101. 605-611 (1997)

    • Related Report
      1996 Annual Research Report
  • [Publications] Y.Kimura,D.Kanda M.Terazima,N.Hirota: "Solvant density Dependence of Translational Diffusion of Transient Radicals in the Medium Density Region of Trifluoromethane" Journal of Physical Chemistry. 101(予定). (1997)

    • Related Report
      1996 Annual Research Report
  • [Publications] 広田 襄: "分子磁性,新しい磁性体と反応制御(伊藤公一編)" 学会出版センター, 23 (1996)

    • Related Report
      1996 Annual Research Report

URL: 

Published: 1996-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi