Radical Formation Initiated by the Biphotonic Excitation of Acridone
Radical Formation Initiated by the Biphotonic Excitation of Acridone
复制标题
吖啶酮双光子激发引发自由基形成
DOI：
10.1246/bcsj.46.3373
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发表时间：
1973
影响因子：
4
通讯作者：
M. Koizumi
中科院分区：
文献类型：
--
作者：
Y. Miyashita;S. Niizuma;H. Kokubun;M. Koizumi
人们发现，当吖啶酮作为敏化剂溶解时，在乙醇刚性溶剂（77 K）和聚乙烯醇（PVA）薄膜（77 K，室温下）中会发生醇自由基的光化学形成。现已确定吖啶酮通过逐步吸收两个光子产生自由基，从醇分子中夺取氢原子，这称为自由基反应机理，缩写为R-R机理。通过测定吖啶酮的能级并检查反应的波长依赖性来估计自由基形成所需的能量。对于乙醇 (77 K)、PVA (77 K) 和 PVA（室温），它们有所不同，可能是由于笼效应。 R-R机制的特点与能量转移型（E-T机制）的特征进行了比较，其中能量从溶质的高级三重态转移到溶剂分子。当将解离能较低的碘甲烷添加到吖啶酮（77 K）的乙醇溶液中时...
The photochemical formation of alcohol radical has been found to occur in the rigid solvent of ethanol (77 K) and in the polyvinyl alcohol (PVA) film (77 K and at room temperature), when acridone is dissolved as a sensitizer. It has been established that by absorbing two photons stepwise acridone gives rise to radicals which abstract hydrogen atoms from alcohol molecules, this being called the radical reaction mechanism and abbreviated as R-R mechanism. The energies necessary for the radical formation were estimated by determining energy levels of acridone and examining the wavelength dependence of the reaction. They differed for ethanol (77 K), PVA (77 K) and PVA (room temp.), perhaps due to the cage effect. The feature of the R-R mechanism has been compared with that of the energy transfer type (E-T mechanism) in which the energy is transferred from the higher triplet of solute to solvent molecules. When methyl iodide with a lower dissociation energy is added to an ethanol solution of acridone (77 K) an...