266nm激光作用下对溴甲苯多光子电离质谱的研究  

Study on multiphoton ionization mass spectra of p-bromotoluene at 266 nm laser radiation

作　　者：宋宝[1] 孔祥和[1] 柳玉梅 郎济刚[1] 宿光勇[1] 张树东[1] 

机构地区：[1]曲阜师范大学物理工程学院,山东曲阜273165 [2]张店区铝城第二中学,山东淄博255072

出　　处：《物理实验》2009年第7期9-13,共5页Physics Experimentation

基　　金：曲阜师范大学博士科研启动基金资助

摘　　要：利用266 nm激光作为光源研究了对溴甲苯分子的多光子电离解离,得到了对溴甲苯的多光子电离飞行时间质谱.实验测得了部分碎片离子占总离子信号的分支比对激光强度的依赖关系,分析了对溴甲苯分子的多光子电离解离机理,讨论了C7H7+,C6H+,C5H5+等碎片离子的可能形成过程.结果表明,碎片离子主要是经过离子离解阶梯模式产生.对实验中观测到的由激光强度变化引起的质谱峰值漂移现象作了说明.Using 266 nm laser as excitation source, the multiphoton ionization and dissociation （MPID） of p-bromotoluene is studied, and time-of-flight mass spectra of multiphoton ionization of p-bromotoluene are obtained. The percentage of part fragment ions to the total ion current and the laser intensity dependence of the molecule are measured. Based on the experimental results, the multipho- ton ionization fragmentation （MPIF） mechanism of p-bromotoluene is analyzed, some formation process of the fragment cations are diccussed, i.e. C7H7^＋ , C6H^＋ , C5H5^＋ etc. The conclusion is that most of ion fragments are produced by ion-fragment dissociation staircase. The shift of the peak positions of mass spectra has been attributed to the laser intensity change.

关 键 词：对溴甲苯 飞行时间质谱 多光子电离解离 卓鎓离子 

分 类 号：O562[理学—原子与分子物理]