不同振动态的CCl_2(A^1B_1)被醇和酮猝灭的动力学  

The Collisional Quenching of CCl_2(A^1B_1) in Different Vibrational States by Alcohols and Ketones

作　　者：高义德[1] 陈 杨学良[1] 陈从香[1] 

机构地区：[1]中国科学院选键化学开放实验室

出　　处：《高等学校化学学报》2002年第7期1339-1342,共4页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金重点项目 (批准号 :10 0 3 2 0 5 0 );国家自然科学基金 (批准号 :2 9973 0 3 8);国家重点基础研究专项基金 (批准号 :G19990 75 3 0 4)资助

摘　　要：对 CCl4 /Ar进行混合气体直流脉冲放电产生 CCl2 自由基 ,再分别用 5 5 0 .5 6,5 41 .5 2 ,5 3 2 .2 5 ,5 2 4.3 1 ,5 2 3 .82和 5 2 3 .2 7nm激光将电子基态 CCl2 激励到激发态 A1 B1 的 (0 ,3 ,0 ) ,(0 ,4,0 ) ,(1 ,3 ,0 ) ,(0 ,6,0 ) ,(1 ,4,0 )和 (2 ,2 ,0 )振动态 ,通过检测激发态 A1 B1 CCl2 的不同振动态的时间分辨荧光信号 (呈双指数衰减 ) ,测得室温下 A1 B1 CCl2 的不同振动态被醇类和酮类分子猝灭的实验结果 ,用三能级模型分析处理实验数据 ,获得态分辨速率常数 k A 和 ka 值 .结果表明 ,其速率常数与振动态的关系并不明显 .CCl 2 free radicals were produced by dc discharge of CCl 4(in Ar). Ground electronic state CCl 2 radical was electronically excited to A 1B 1 (0,3,0), (0,4,0), (1,3,0), (0,6,0), (1,4,0) and (2,2,0) vibronic states by Nd∶YAG laser pumped dye laser at 550.56, 541.52, 532.25, 524.31, 523.82 and 523.37 nm respectively. The experimental quenching data of CCl 2( A 1B 1 and a 3B 1) by alcohols and ketones were obtained by observing time resolved fluorescence from the excited CCl 2 radicals transition, which showed a superposition of two exponential decay components. The state resolved rate constants k A and k a were acquired by analyzing and dealing with these data by using three level model, which was put forward by us. It is found that the quenching rate constant is not dependent on the vibrational state.

关 键 词：振动态 醇 酮 动力学 猝灭速率常数 三能级模型 CCL2自由基 化学反应 二氯卡宾 

分 类 号：O643.1[理学—物理化学]