物理化学学报 >> 1996, Vol. 12 >> Issue (03): 239 -244 .doi: 10.3866/PKU.WHXB19960310

研究论文 上一篇    下一篇

H2 + CN(n=0,1)→H + HCN振动选态反应

曹晓燕,李宗和,刘若庄   

  1. 北京师范大学化学系,北京 100875
  • 收稿日期:1995-07-25 修回日期:1995-10-11 发布日期:1996-03-15
  • 通讯作者: 刘若庄

State-selected Reaction Studies on H2 + CN(n=0,1)→H + HCN

Cao Xiao-Yan,Li Zong-He,Liu Ruo-Zhuang   

  1. Department of Chemsitry,Beijing Normal University,Beijing 100875
  • Received:1995-07-25 Revised:1995-10-11 Published:1996-03-15
  • Contact: Liu Ruo-Zhuang

摘要:

用从头算方法获得了H2+CN反应的内禀反应坐标(IRC).沿着IRC,计算了各垂直于IRC的简正模所对应的频率(ω)以及沿IRC运动与垂直于IRC运动的简正模之间的耦合常数(BKF). 根据传统过渡态、变分过渡态理论和选态公式,计算了nCN=0及nCN=1时反应的速率常数,并得到了和实验相一致的结果. 还计算了nCH=1及nCN=1时H+HCN→H2+CN反应速率常数. 可供实验工作者参考.

关键词: 氰基, 内禀反应坐标(IRC), 反应速率常数, 选态反应

Abstract:

In this paper, based on ab initio with gradient technique, the intrinsic reaction coordinate (IRC) of the reaction CN+H2→H+HCN has been traced by using numerical method. Along the IRC, the coupling constants between the IRC and vibrations orthogonal to it, and the vibrational frequencies have all been investigated. The theoretical rate constants for vibrationally excited reactants nCN =1 or nCN = 0 in the conventional transition state theory, variational transition state theory and with tunneling corrections have been calculated. They are in good agreement with experimental results. HCN(nCN=1, nCH=1)+H→CN+H2 reaction rate constants have also been calculated in this paper, and the theoretical results are for experimental reference only.

Key words: Cyanide, Intrinsic reaction coordinate(IRC), Reaction rate constant, State-selected reaction