物理化学学报 >> 1998, Vol. 14 >> Issue (03): 193-197.doi: 10.3866/PKU.WHXB19980301

研究论文    下一篇

氰基苯阴离子与CO2间的内球电子转移

郭建新, 王彦妮, 张启元   

  1. 分子动态与稳态结构国家重点实验室，中国科学院化学研究所，北京 100080
  • 收稿日期:1997-06-16 修回日期:1997-08-23 发布日期:1998-03-15
  • 通讯作者: 张启元

The Inner-sphere Electron Transfer from Benzenitrile Anion Radical to Carbon Dioxide

Guo Jian-Xin, Wang Yan-Ni, Zhang Qi-Yuan   

  1. State Key Laboratory for Structural Chemistry of Unstable and Stable species,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080
  • Received:1997-06-16 Revised:1997-08-23 Published:1998-03-15
  • Contact: Zhang Qi-Yuan

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摘要：

用半经验AM1方法以及从头算方法在3-21G和6－31G*基组水平上研究了从氰基苯阴离子到CO2的电子转移过程．结果表明，对于先驱物(precursor), 三种计算方法得出的给体、受体间的距离分别为0.2728nm(AM1)、0.2479nm（UHF/3-21G）和0.2769nm(UHF/6-31G*)．在这样短的距离内给体的HOMO与受体的LUMO轨道具有相当程度的重叠，应产生较强的相互作用，说明此反应是内球电子转移反应，从而解释了此类体系的电子转移反应不符合Marcus理论的原因．计算给出先驱物的束缚能为0.19eV(AM1)和0.26eV(6-31G*).

关键词: 内球电子转移, AMI, 从头算方法

Abstract:

The process of electron transfer (ET) from benzenitrile radical anion to carbon dioxide is studied by the quantum chemical semiempirical AM1 and ab initio methods on 3-21G and parlization 6-21G* levels. The results showed that the donor-to-acceptor distance in the precursor is 0.2728 nm for AM 1, 0.2479 nm for UHF/3-21G and 0.2769 nm for UHF/6-31G*. In such a short distance, the HOMO in donor and LUMO in acceptor will approach and overlap considerably, which correspondes to a nonneghgrble interaction between the donor and the acceptor. It showed that this ET reaction is not a simple out-sphere but rather an inner-sphere process, the violation of Marcus theory for this reaction can therefore be explained reasonabley. The binding energy of the Precursor is calculated to be 0. 19 eV for AM1 and 0.26 eV for ab initio 6-31G* level.

Key words: Inner-sphere electron transfer, AMl, Ab initio method