乙二醇均相溶液中苊醌三重激发态淬灭反应的TR-ESR研究  

A TR-ESR study on the quenching reaction of the excited triplet state of acenaphthenequinone in Ethylene glycol homogeneous solution

作　　者：许新胜[1] 刘毅[1] 朱光来[1] 崔执凤[1] 

机构地区：[1]安徽师范大学原子与分子物理研究所,芜湖241000

出　　处：《原子与分子物理学报》2011年第2期282-286,共5页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(20903004);安徽高校省级自然科学研究重点项目(KJ2010A145)

摘　　要：利用时间分辨电子自旋共振(TR-ESR)方法,研究了乙二醇(EG)均相溶液中稳定自由基TEMPO和生物抗氧化剂维生素C(VC)对苊醌(ACQ)激发三重态~3ACQ~*的淬灭反应.光解ACQ/EG体系,观察到苊醌中性自由基ACQH~·和乙二醇烷基自由基的发射/吸收+发射(E/A+E)的CIDEP信号,ACQH~·和CH_2(OH)CHOH由~3ACQ~*从EG上夺氢生成.光解ACQ/TEMPO/EG体系,~3ACQ~*与TEMPO相互作用将极化转移给TEMPO.光解ACQ/VC/EG体系,~3ACQ~*除了从EG上夺氢外,还从VC上夺氢生成VC负离子基As^(·-).较强的As^(·-)的CIDEP信号表明VC对~3ACQ~*有明显的淬灭作用.The reaction mechanisms of the excited triplet of acenaphthenequinone （3ACQ＂） quenched by stable radical TEMPO and biological antloxidant vitamin C（VC） in ethylene glycol （EG） homogeneous solution have been studied by using TR-ESR method in this paper. The photolysis of acenaphthenequinone （ACQ） in EG gave the emissive/absorptive ＋ emissive CIDEP signal of ACQ neutral radical Ac- QH＊ and EG ketyl radical CH2 （OH）C HOH, which were generated by a hydrogen abstraction of 3ACQ. from solvent EG. During the photolysis of ACQ/TEMPO/EG system, the interaction between 3 ACQ＊ and TEMPO made the spin polarization transfer from the former to the latter. For ACQ/VC/EG system, 3ACQ＊ abstracted hydrogen atoms not only from solvent EG but also from VC. The strong CIDEP signal of VC anion radical As＊- suggested that VC is an effective quencher to 3 ACQ＊.

关 键 词：苊醌 维生素C TEMPO TR-ESR CIDEP 

分 类 号：O562.32[理学—原子与分子物理] O643.12[理学—物理]