生物体系中电子转移机理的理论研究——Ⅰ.一种计算电子转移的方法及在螺环化合物中的应用  

Theoretical Study on the Electron Transfer in Biological SystemsⅠ. A Method for Calculating the Electron Transfer and Its Application in Spiro π - Electron System

作　　者：翟宇峰[1] 顾健德[1] 蒋华良[1] 陈建忠 朱维良 陈凯先[1] 嵇汝运[1] 

机构地区：[1]中国科学院上海药物研究所,上海200031

出　　处：《化学学报》1998年第11期1081-1086,共6页Acta Chimica Sinica

摘　　要：应用“相应轨道变换”和“广义”密度矩阵的方法,向MOPAC程序包中加入了新的功能,使其能处理电子转移反应中的部分参数.然后用此程序包中AMI方法对具有螺环结构的分子进行处理,计算了化合物在不同外加电场强度下的势能面、反应热ΔE,重组能λ及电子转移矩阵元V_(AB),结果表明,λ,V_(AB)受外加电场的影响较小,而ΔE则与之成正比.对标题化合物1的计算结果也同ab initio法的结果进行了比较,发现其变化趋势完全一致,这说明本方法在计算电子转移方面是可靠的.与ab initio方法相比,本程序不仅适用于计算较大体系(如生物大分子),而且还具有速度快,耗时少的优点.We have added a new function to the MOPAC program package by employing the methods of corresponding orbital transformation and generalized density matrix and developed a new program called MOPAC - ET, which can deal with the electron transfer reactions. We have also calculated a molecule with spiro π - electronic structure by use of this method and obtained its potential energy surface, exothermicity △E, reorganization energy λ and electron transfer matrix elements VAB. The results indicate that VAB and λ are not obviously affected by the outer electric field while the △E is directly proportional to it. The calculated results of title compound 1 were also compared with that from ab initio method. It was found that our results are consistent with that calculated by ab initio method. This approved the reliability of the program MOPAC - ET. In addition to this, the program has advantages of faster speed and less time consuming over the ab initio methods, thereby can be used to simulate the electron transfer for the large systems such as biological macromolecules.

关 键 词：电子转移 生物体系 AM1 螺环化合物 机理 

分 类 号：O621.13[理学—有机化学]