Photochemical Reaction of Metal Complexes Studied by Advanced EPR

利用先进 EPR 研究金属配合物的光化学反应

基本信息

批准号：
07044058
负责人：
YAMAUCHI Seigo
金额：
$ 3.84万
依托单位：
Institute of Chemical Reaction Science Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

In this study we developed new EPR machines and studied photophysics and photochemistry of metal complexes with these laboratory-made EPR apparatus. The following results were obtained :1) The Fourier transform (FT) EPR machine was constructed by modifying our spin echo system for analyzes of photochemical reactions. The experiments of high time-resolution (10ns) and multi-dimensional modes were made possible with this machine.2) In Mobius' laboratory, the W-band EPR machine was constructed and used both in time-resolved and pulsed modes, which has the higher time-resolution (5ns).3) The electron spin polarization transfer was verified for the firsr time in the triplet-doublet system, where we used excited triplet metalloporphyrins and nitroxide radicals. By means of this technique we measured the spin-lattice relaxation times of radicals and observed the spectra of non-polarized radicals.4) The two-dimensional nutation method was applied for the first time in the transient EPR experiment ; mettalloporphyrin-quinone in micellar system. The photochemical intermediate was separated spectroscopically from the radicals and definitely assigned as an ion pair.5) New microwave-pulse sequences were developed and applied to the study of molecular dynamics of metallofullerenes. Temperature dependence of the signal was examined and analyzed in terms of molecular liblations and spin dynamics.6) Triplet-radical pair systems were constructed with metalloporphyrins ligated by pyridinyl-nitroxied radicals. Two kinds of EPR signals were separeted by the W-band EPR technique and assigned by the two-dimensional nutation technique as those of the excited quartet and doublet states.In addition to these scienfically important results, We succeeded in making acontract between our Laboratory and Department of Physics of Berlin Free University and in holding the international Sendai Symposium twice.

在这项研究中，我们开发了新的EPR机器，并使用这些实验室制造的EPR设备研究了金属复合物的光体物理学和光化学。获得以下结果：1）通过修改我们的自旋回波系统以分析光化学反应，构建了傅立叶变换（FT）EPR机器。使用这台计算机的较高时间分辨率（10N）和多维模式的实验。金属核蛋白和氮氧化物自由基。通过这项技术，我们测量了自由基的自旋晶格松弛时间，并观察到了非极化自由基的光谱。4）在瞬态EPR实验中，首次应用了二维属性方法；胶束系统中的荟萃磷脂素酮。将光化学中间体与自由基分开，绝对分配为离子对。5）开发了新的微波脉冲序列，并应用于金属氟烯烯的分子动力学研究。检查了信号的温度依赖性，并根据分子涂层和自旋动力学进行了分析。6）三翼丁基二硝基自由基绑扎的三丁基蛋白构建了三翼。通过W频段EPR技术将两种EPR信号分解，并由二维的营养技术分配为激发四重奏和双重持续状态的EPR技术。除了这些非常重要的结果外，我们成功地在柏林大学的实验室和国际Sendai Sendai Sendai Symposium Twice Twice中取得了成功。