Development of the CIDNP-detected Electron Spin Resonance Apparatus for the Aid of Investigation of Radical Pairs

开发 CIDNP 检测的电子自旋共振仪以帮助研究自由基对

• 批准号: 03554013
• 负责人: AZUMI Tohru
• 金额: $ 6.46万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03554013/
• 关键词: CIDNP; ESR; CIDNP-detected ESR; SNP; DNP; dichlorobenzoquinone; Radical Pair; 反応中間体; 遊離ラジカル; ベンゾキノン; CIDEP; 交差緩和; ベンズアルデヒド

In most of chemical reactions in solution, the whole fate of the reaction path is governed by the small interaction that is operative within a short lifetime of radical pairs. In this respect one whishes to observe the spectrum of radical pairs and analyze it to fully understand chemical reactions. However, in any conventional spectroscopy, the spectrum due to radical pairs and that due to free radicals cannot be separately observed.The CIDNP-detected ESR spectroscopy has been developed in order to separately obseve the ESR spectrum of radical pairs and that of free radicals. We have further tried to extend this spectroscopy to time-resolved spectroscopy.By this new spectroscopy, a lot of chemical reactions have been investigated. As an example, the photo-induced hydrogen abstraction reaction of dichlorobenzoquinone has been investigated. It has found that the hydroxybenzoquinone radical that exists as a radical pair and that exists as a free radical are different. This amazing conclusion can never be obtained by any other spectroscopic means. Further, the lifetime of radical pairs was determined as 20 ns.

在溶液中的大多数化学反应中，反应路径的整个命运由在自由基对的短寿命内起作用的小相互作用决定。在这方面，人们希望观察自由基对的光谱，并对其进行分析，以充分了解化学反应。然而，在任何常规的光谱学中，由于自由基对的光谱和由于自由基的光谱不能被分开观察，CIDNP检测的ESR光谱已经被开发，以分开观察自由基对的ESR光谱和自由基的ESR光谱。我们还尝试将这种光谱学扩展到时间分辨光谱学，并利用这种新的光谱学研究了许多化学反应。以二氯苯醌的光诱导夺氢反应为例进行了研究。已经发现，作为自由基对存在的羟基苯醌自由基和作为自由基存在的羟基苯醌自由基是不同的。这个惊人的结论是任何其他光谱手段都无法得到的。此外，自由基对的寿命被确定为20 ns。

项目成果

Q.Meng, et al.: "Triplet Mechanism of CIDNP in the Photolysis of Benzoquinones As Studied by Dynamic Nuclear Polarization." J.Phys.Chem.97. 1265-1269 (1993)

Q.Meng 等人：“通过动态核极化研究 CIDNP 在苯醌光解中的三重态机制”。

Hisayuki Miki,et al.: "Phosphorescence from the Triplet Spin Sublevels of a Hexanuclear Molybdenum(II) Chloride Cluster Ion,[Mo_6Cl_<14>]^<2->.Relative Radiative Rate Constants for Emitting Sublevels." The Journal of Physical Chemistry.

Hisayuki Miki 等人：“六核氯化钼 (II) 簇离子的三重态自旋亚能级的磷光，[Mo_6Cl_<14>]^<2->。发射亚能级的相对辐射率常数。”

H.Miki,et al.: "Effect of the Ligand-Field Strength on the Radiative Properties of the Ligand-Localized ^3ππ^* State of…" J.Phys.Chem.97. 11175-11179 (1993)

H.Miki 等人：“配体场强度对配体局域 ^3ππ^* 状态辐射特性的影响”J.Phys.Chem.97 (1993)。

K.Maeda, et al.: "Phosphorescence from the Delocalized Triplet State of Polysilylenes." J.Phys.Chem.97. 12144-12146 (1993)

K.Maeda 等人：“聚硅烯离域三重态的磷光”。

H.Miki,et al.: "Effect of the Ligand-Field Strength on the Radiative Properties of the Ligand-Localized ^3ππ^* State of Rhodium Complexes with..." J.Phys.Chem.97. 11175-11179 (1993)

H.Miki 等人：“配体场强度对配体局域 ^3ππ^* 铑配合物状态辐射特性的影响”J.Phys.Chem.97（ 1993）