| 大气臭氧损耗中双自由基反应机理的量子化学研究 |
| 摘要点击 632 全文点击 1464 投稿时间：1995-07-14 |
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| 中文关键词 双自由基 臭氧损耗 反应机理 |
| 英文关键词 biradical loss of ozne reaction mechanism |
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| 中文摘要 |
| 用量子化学RHF理论方法研究了单重态双自由基NH、CH2、CCl2与大气臭氧O3的反应机理。在3-21G水平上用梯度解析技术优化了上述反应的反应物、中间体和产物构型,6-31G或6-21G计算能量。得到了各构型的有关结构数据。计算表明:上述反应分2步进行,双自由基先与O3反应生成稳定的中间体,然后在光照条件下中间体分解为HNO、H2CO和Cl2CO等稳定分子。从动力学看,2步反应分别为[π4s+W2s]和[π2s+π2s]反应,热力学上也是允许的。通过本项研究,试图提供一种不计算反应过渡态,将热力学分析和Woodward-Hoffmann规则相结合研究复杂反应的方法。 |
| 英文摘要 |
| The reaction mechanisms of the singlet biradicals NH,CH2, CCl2 with ozone in the atmosphere have been studied using RHF method of quantum chemistry. The geometries of the reactants, intermediates and products of the above reactions are optimized with the gradient technique at the 3-21G level, their energies have been calculated at the 6-31G or 6-21G level. The structure data of all species have been obtained. The calculated results show that there are two stages in the above reactions, the reactions of the biradicals with ozone take place first to form the stable intermediates, then the intermediates are decomposed by illuminating to the stable molecules HNO,H2CO and Cl2CO etc., respectively. In terms of dynamics two reactions in two stages belong to the types [π4s+W2s] and [π2s+π2s], respectively, and they are permited thermedynamically. In this study, a method to investigate complicated reaction based on the combining thermodynamics with Woodward-Hoffmann approach without calculation of transition state was attempted to provide by authors. |
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