物理化学学报 >> 1985, Vol. 1 >> Issue (06): 547-555.doi: 10.3866/PKU.WHXB19850608

研究论文 上一篇    下一篇

排斥作用对光分解产物转动分布的重要性

吕日昌   

  1. 中国科学院大连化学物理研究所
  • 收稿日期:1985-03-09 修回日期:1985-07-01 发布日期:1985-12-15
  • 通讯作者: 吕日昌

CONTRIBUTION OF THE REPULSIVE INTERACTION BETWEEN FRAGMENTS TO ROTATIONAL DISTRIBUTION OF THE FRAGMENTS IN PHOTOLYSIS

Lü Richang   

  1. Dalian Institute of Chemical Physics, Chinese Academy of Sciences
  • Received:1985-03-09 Revised:1985-07-01 Published:1985-12-15
  • Contact: Lü Richang

摘要: 本文用一个简单的经典力学模型, 对ClCN, BrCN, C_2N_2, C_4N_2等一系列分子的光分解产物的转动分布进行了分析, 着重讨论了光解碎片间的相互排斥对它们的转动分布的作用。模型分析和实验结果的比较表明, 这种经典模型对于理解光解过程的动力学行为是很有用的。

Abstract: any studies on rotational distribution of photofragments have been done both in experimental and in theoretical aspects during the past decade, but eomparisions of the theoretical results with the experimental ones remain few and far between. An attempt has been made to emphasize the effects of the repulsive interaction between photofragments on their rotational distribution. A simple classical model was postulated and the interpretation with this model is qualitatively in good ag- reement with a series of experimental observations listed in Table 1. Based on this model, the angular momentum of the photofragments could be divided into two parts: one from the rotation of the parent molecule; the cooling of the parent molecules in a supersonic jet could only affect the first part. The second part depends mainly upon the nature of the dissociative potential surface. Using this simple model, one can also obtain some dynamic informations including some characteristics of the potential surface. A number of examples are given in the discussion, which show that the interpretation with this model is fairly consistent with the results observed in the photolysis of ClCN, BrCN, C_4N_2 etc. in effusive or supersonic molecular beams. This qualitative agreement means that the classical model is helpful if the quantum theory on the rotational distribution of photofragments is not available in practice.