非对称笼间电子迁移异构体与电场诱导电子迁移  

Asymmetrical Inter-Cage Electron Transfer Electromers and Their Transfer Characteristics under Electric Fields

作　　者：王银锋[1] 黄俭根[1] 周光培[1] 李志儒[2] 

机构地区：[1]井冈山大学化学化工学院、应用化学研究所、江西省配位化学重点实验室,江西吉安343009 [2]吉林大学理论化学研究所、理论计算化学国家重点实验室,长春130023

出　　处：《物理化学学报》2012年第11期2574-2580,共7页Acta Physico-Chimica Sinica

基　　金：江西省科技厅自然科学基金(20114BAB213007);江西省教育厅自然科学基金(GJJ12486);国家自然科学基金(21173098);井冈山大学博士启动基金(JZ10045);吉林大学理论计算化学国家重点实验室开放课题基金资助项目~~

摘　　要：基于密度泛函理论研究了非对称双笼型单分子溶剂化电子e-@C24F22(NH)2C20F18(1、2和3),进一步展示了我们提出的一种新型电子异构体——(非对称型的)笼间电子迁移异构体.1、2和3具有显著不同的偶极矩.由于都存在两个氧化还原中心,它们属于一种非金属型的新型Robin-DayII-III分子.对于1和3,额外电子分别定域在C24F22和C20F18笼里(Robin-DayII);对于2,额外电子则离域于两个非对称的笼中(Robin-DayIII).值得注意的是,在y轴方向上外加-0.0004和-0.0008a.u.的临界电场(Ec)时可分别使1的额外电子从C24F22笼中部分和全部地迁移到C20F18笼中,即实现从1到2再到3的转化;当Ec为0.0004a.u.时,3的额外电子从C20F18笼中全部迁移到了C24F22笼中,即3未经过2直接转化成了1.The asymmetrical, double-cage-shaped, single molecular solvated electron compounds e-@C24F22（NH）2C20F18 （1, 2, and 3） were investigated based on density functional theory （DFT）. This work revealed a novel species of electromer consisting of asymmetrical inter-cage electron-transfer isomers. These inter-cage electron-transfer isomers belong to a new form of Robin-Day class II-III molecules. 1 and 3 are Robin-Day class II, with the excess electron inside the C24F22 and C20F18 cages respectively, while 2 is class III with the excess electron inside both cages. These electromers were found to exhibit significantly different dipole moments. The application of external electric fields of -0.0004 or -0.0008 a.u. in the y-axis direction of 1 resulted in either partial or whole transfer of the excess electron from C24F22 to C20F18, allowing conversion from 1 to 2 or 3. An Ec value of 0.0004 a.u. was determined, indicating that the excess electron can wholly transfer from the C20F18 cage to C24F22, resulting in conversion from 3 to 1 without going through 2.

关 键 词：电场诱导 Robin-Day分子 单分子溶剂化电子 电子异构体 不对称笼间电子迁移 

分 类 号：O641[理学—物理化学]