Reaction Control of Photochemical Processes in Liquid Crystalline Phases

液晶相光化学过程的反应控制

基本信息

批准号：
60470082
负责人：
MATSUO Taku
金额：
$ 4.42万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1986
项目状态：
已结题

项目摘要

Attempts have been made to control reaction rates of photochemical processes, such as energy-transfer and electron-transfer, in liquid crystals and bilayer-membrane systems.(1) Remarkable electric field effects were observed with sensitized fluorescence intensities of a perylene derivative, when rectangular AC waves (up to 10 <V_(0-p)> ) were applied to liquid crystal cells containing a sensitizer and an acceptor (the perylene derivative) as the guest molecules. Measurements of the fluorescence lifetime of the sensitizer indicated that the rates of energy transfer were independent of the electric fields. The electric field effects completely changed the sign when the intensity variation detected at vertical direction was compared with that at the horizontal direction with respect to the plane of the liquid crystal cell. The observed electric field effects on the sensitized fluorescence were consequently ascribed to the orientation control of transition dipolemoment of the acceptor thro … More ugh molecular alignments of the liquid crystal.(2) As to the electron-transfer in bilayer membrane systems, effects of external magnetic fields on laser-induced electron-transfer rates were investigated by the use of porphyrin-viologen linked systems. Rates of reverse electron transfer in the photogenerated intramolecular ion radical pair, as originated from quenching of porphyrin triplet by viologen, were remarkably suppressed at above 0.1 T. In addition, amphiphilic viologen molecular assemblies were found to help charge-separation of the photoinduced, intramolecular electron transfer in sensitizer-acceptor linked system incorporated into the molecular assemblies. Construction of hole-transport system was also attempted by the use of double-chain ammonium amphiphile with carbazole moiety, which afforded extremely long-living charge-separated states on laser excitation. All of these phenomena were ascribed to cooperativity effects of aligned acceptor (or donor) units, which permit electron (or hole) migration via electron exchange mechanism. Less

Attempts have been made to control reaction rates of photochemical processes, such as energy-transfer and electronic-transfer, in liquid crystals and bilayer-membrane systems.(1) Remarkable electric field effects were observed with sensitive fluorescence intensities of a perylene derivative, when rectangular AC waves (up to 10 <V_(0-p)> ) were applied to liquid crystal cells containing a sensitive and an acceptor (the佩里烯衍生物）作为来宾分子。灵敏度的荧光寿命的测量表明，能量转移的速率与电场无关。将在垂直方向上检测到强度变化与在水平方向上相对于液晶细胞平面的强度变化时，电场效应完全改变。因此，观察到的电场对敏感荧光的电场影响归因于受体的过渡偶像植物的取向控制，这是……液晶液晶的更多UGH分子对齐。（2）关于双层膜系统中的电子转移，对激光诱导的电视率的portermigin portervers for Insperfrand portervers the waysrand for n he versight率的效果。 Rates of reverse electron transfer in the photogenerated intramolecular ion radical pair, as originated from quenching of porphyrin triplet by viologen, were remarkably suppressed at above 0.1 T. In addition, amphiphilic viologen molecular assemblies were found to help charge-separation of the photoinduced, intramolecular electron transfer in sensor-acceptor linked system incorporated into the molecular assemblies.还尝试了使用双链铵Ammhyphile和Carbazole部分的建造孔 - 通道系统，该铵在激光兴奋中提供了非常长的电荷分离状态。所有这些现象都归因于对齐受体（或供体）单位的合作效应，该单位允许通过电子交换机制进行电子（或孔）迁移。较少的