高等学校化学学报

高等学校化学学报 ›› 1994, Vol. 15 ›› Issue (10): 1525-1528.

• 论文 • 上一篇    下一篇

CH(B2Σ－)和卤代甲烷、CS2、O2及Ar碰撞过程动力学研究

陈从香, 盛悦, 戴继勋, 马兴孝   

  1. 中国科学技术大学化学物理系, 合肥, 230026
  • 收稿日期:1993-11-06 修回日期:1994-03-21 出版日期:1994-10-24 发布日期:1994-10-24
  • 通讯作者: 陈从香,男,53岁,副教授.
  • 作者简介:陈从香,男,53岁,副教授.
  • 基金资助:

    国家自然科学基金

The Kinetic Study on Collisional Quenching of CH(B2Σ-)by Halomethane,CS2,O2 and Ar Molecules

CHEN Cong-Xiang, SHENG Yue, DAI Ji-Xun, MA Xing-Xiao   

  1. Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026
  • Received:1993-11-06 Revised:1994-03-21 Online:1994-10-24 Published:1994-10-24

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摘要： 用四倍频YAG激光(266nm)光解CHBr3产生CH(B2Σ-)自由基,通过测量自发辐射CH(B→X)的时间分辨信号测得室温下CH(B→X)被卤代甲烷、CS2、O2及Ar的猝灭速率常数(×10-10cm3·molec-1·s-1)分别为4.4±0.7(CH2Cl2)、5.2±0.4(CHCl3)、5.0±0.7(CCl4)、8.2±0.3(CHBr3)、7.9±0.7(CS2)、0.19±0.02(O2)及(1.1±0.1)×10-2(Ar).结果表明,除O2外,其它猝灭剂对CH(B)的猝灭速率常数均大于对CH(A)的。对卤代甲烷分子,猝灭速率常数显示了因Cl原子数增加而增加的趋势。

关键词: CH自由基, 猝灭, 动力学

Abstract: CH(B2Σ-)radical was produced by quadrupuled YAGlaser(266 nm)photolysis of CHBr3 molecules.The quenching rate constants by halomethane(CH2Cl2, CHCl3, CCl4 and CHBr3), CS2, O2, and Ar were determined at room temperature by monitoring the time-resolved emission CH(B→X)signals.The measured results(in10-10cm3·molec-1·s-1)are 4.4±0.7(CH2Cl2), 5.2±0.4(CHCl3), 5.0±0.7(CCl4), 8.2±0.3(CHBr3), 7. 9±0.7(CS2), 0.19±0.02(O2), and(1.1±0.1)×10-2(Ar), respectively。It is shown that the quenching rate constant of CH(B)is faster than that of CH(A)except for O2 molecule.The quenching rate constant of CH(B)increases with increasing the number of chlorine atoms contained in chloromethane molecules and an interpretation of this result based on complex model is presented.

Key words: CH radical, Quenching, Kinetics