New development of the researches in the magnetic field effects on chemical reactions

磁场对化学反应影响研究新进展

• 批准号: 12440172
• 负责人: HAYASHI Hisaharu
• 金额: $ 7.74万
• 依托单位: RIKEN (Institute of Physical and Chemical Reserch)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12440172/
• 关键词: magnetic field effect; pulsed magnet; radical pair lifetime; escape radical yield; ultra-high magnetic field effect; ps-laser photolysis apparatus; sextet-quartet conversion; relaxation mechanism; ピコ秒レーザーホトリシス; ラジカル対; トリラジカル; 光還元反応

We have tried to find new magnetic field effects on chemical reactions, extending our studies to unexplored regions of this field. We have succeeded in finding the foliowing new effects :1.We developed a pulscd magnet, which was suitable for the measurements of chemical reactions at room temperature. Using this magnet and our ns-laser photolysis apparatus, we have frst found many new effects on radical pair lifetimes and escape radical yields for some photochemical reactions in micellar and organic solutions under ultra-high magnetic fields of 17-30T. We have interpreted the effects observed in micellar solutions under fields of 0-30 T in terms of the relaxation mechanism.2.Because the magnetic field effccts on the yields in fluid organic solutions under fields of 0-30 T could not be explained by the conventional theory, we have dcveloped a new theory with a combination of the Ag and relaxation mechanisms. Using this new theory, we could make a quantitative analysis of the effects.3.We frrst developed a ps-laser photolysis apparatus, which was suitable for the measurement of magnetic field effects on photochemical reactions of usual organic molecules. Using this apparatus and our electromagnet, we have found the effect on the triplet-singlct conversion of a radical pair generated in a fluid solution. We have interpreted this effect in terms of the Ag mechanism.4.Using our ns-laser photolysis apparatus, we have found new magnetic field effects on escaped radical yields in some photochemical reactions in fluid solutions through quartet and sextet states, The latter one is the effect for the highest spin state which has ever been studied so for. We have interpreted these effects in terms of the relaxation mechanism involving the quartet-doublet and sextet-quartet conversions.

我们试图找到新的磁场对化学反应的影响，将我们的研究扩展到这个领域的未开发区域。我们成功地发现了以下新效应：1.研制了一种脉冲磁体，它适用于室温下化学反应的测量。利用这种磁体和我们的ns激光光解装置，我们首次发现了在17 - 30T的超高磁场下，胶束和有机溶液中某些光化学反应的自由基对寿命和逃逸自由基产率的许多新效应。我们用弛豫机制解释了在0 - 30 T磁场下胶束溶液中观察到的效应。2.由于磁场对0 - 30 T磁场下流体有机溶液产率的影响不能用传统理论解释，我们提出了一个结合Ag和弛豫机制的新理论。利用这一新理论，我们可以对这种效应进行定量分析。3.我们首次研制了一套适用于测量磁场对常见有机分子光化学反应影响的ps激光光解装置。利用这个装置和我们的电磁铁，我们发现了在流体溶液中产生的自由基对的三重态-单重态转换的影响。4.利用我们的ns激光光解装置，我们发现了磁场对流体溶液中某些光化学反应中四重态和六重态逃逸自由基产率的新的影响，其中六重态是迄今为止所研究的最高自旋态的影响。我们解释了这些影响的松弛机制，涉及的四重态和六重态四重态转换。

项目成果

森野 勇: "Magnetic Field Effects on the Hydrogen Abstraction Reaction of Triplet 4-Methoxy------"Molecular Physics. (印刷中). (2002)

Isamu Morino：“磁场对三重态 4-甲氧基------的夺氢反应的影响”分子物理学（出版中）。

若狭 雅信: "Re-examination of the Magnetic Field Effects on the Thermal Reactions of Benzyl and -----"Molecular Physics. (印刷中). (2002)

Masanobu Wakasa：“重新检查磁场对苯甲基和 ----- 的热反应的影响”分子物理学（2002 年出版）。

若狭 雅信: "Magnetic Field Effects on the Dynamic Behavior of a Radical Pair as Studied by----------"Chemical Physics Letters. 325・5-6. 343-350 (2000)

Masanobu Wakasa：“磁场对自由基对动态行为的研究——”《化学物理快报》325・5-6（2000）。

森 幸恵: "Spin Chemical Approach Towards Long-Lived Charge-Separated States generated by ------"Bulletin of Chemical Society of Japan. 74・2. 293-304 (2001)

Yukie Mori：“自旋化学方法产生的长寿命电荷分离态”日本化学学会公报74・2（2001）。

I. Morino: "Magnetic Field Effects on the Hydrogen Abstraction Reaction of Triplet 4-Methoxy-benzophenone with Thiophenol as Studied by a Picosecond Laser Flash Photolysis Technique."Molecular physics. (in press). (2002)

I. Morino：“通过皮秒激光闪光光解技术研究磁场对三线态 4-甲氧基二苯甲酮与苯硫酚的夺氢反应的影响。”分子物理学。