9,10-二氰基蒽和杜烯间光诱导电子转移的电荷分离态和电子耦合  

Charge-separated State and Electronic Coupling for Photoinduced Electron Transfer Between 9,10-Dicyanoanthracene and Durene

作　　者：易海波[1] 段晓惠[1] 李象远[1] 杨胜勇[1] 

机构地区：[1]四川大学化工学院,成都610065

出　　处：《高等学校化学学报》2003年第8期1438-1441,共4页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :39970 183);教育部重点科技项目资助

摘　　要：采用从头算方法 ,讨论了 9,1 0 -二氰基蒽 (DCA)和杜烯 (DUR)间光诱导电子转移反应的态 -态跃迁 .考虑基组重叠误差 (BSSE)对相互作用能的校正 ,用 MP2方法优化得到重叠式 [DCA…DUR]配合物的稳定构型 .用单激发组态相互作用 (CIS)方法讨论了 [DCA…DUR]配合物的光诱导电荷分离和电荷复合过程 .根据广义 Mulliken-Hush(GMH)模型 ,计算了电荷复合过程的电子耦合矩阵元 .结果表明 ,[DCA… DUR]配合物的 S0 → S1 和 S0 → S2 跃迁产生了两个强的局域激发态 ,S0 → S3 跃迁直接导致电荷分离态 ,小的振子强度预测该电荷转移 (CT)跃迁是一弱跃迁 ,电荷分离态 S3 衰变到低局域激发态或基态的电荷复合是可能的 .In this work, ab initio and DFT calculations have been performed to investigate the state transitions in photoinduced electron transfer reactions between 9,10-dicyanoanthracene(DCA) and durene(DUR). The face-to-face structure of complex has been optimized by using Mφller-Plesset method, and the counterpoise method is adopted to consider the basis set superposition error correction of interaction energy. Four low-lying excited singlet states of complex have been investigated by using the method of configuration interaction singles(CIS). It is concluded that the transitions from the S 0 state to the S 1 and S 2 states do not lead to the charge separation. The transition from S 0 state to S 3 state is found to produce a charge-separated state directly, but the small oscillator strength indicates that the intensity of the charge transfer(CT) absorption is probably quite weak. The decays of charge-separated state to the locally excited states and the ground state have been examined. According to the generalized Mulliken-Hush model, the electronic coupling matrix elements in the charge recombination(CR) processes have been evaluated. Our investigation makes it clear that the direct CT absorption is rather weak, while the CR process from the CT state to a locally excited state or to the ground state seems possible.

关 键 词：9 10-二氰基蒽 杜烯 光诱导电子转移 电荷分离态 电子耦合 矩阵元 激发态 从头算方法 配合物 

分 类 号：O625.154[理学—有机化学] O625.11[理学—化学]