2-氨基-3-苯并恶唑喹啉水复合物激发态分子内与分子间质子转移的竞争机理

Competitive Mechanism of Intramolecular and Intermolecular Proton Transfer of 2-Amino-3-(2′-benzoxazolyl)-quinoline Water Complex in Excited State

基于密度泛函与含时密度泛函理论方法,研究2-氨基-3-苯并恶唑喹啉(ABO)水复合物(ABO-H_2O)激发态分子内与分子间质子转移的竞争机理.结果表明:ABO-H_2O复合物中存在一个分子内的氢键和两个分子间的氢键;基态ABO-H_2O复合物被激发至第一电子激发态后,仅需越过一个34.157kJ/mol能垒,复合物即可发生激发态分子内的质子转移反应;ABO-H_2O复合物激发态分子间的双质子转移过程中存在一个63.585kJ/mol能垒;在第一电子激发态上,ABO-H_2O复合物中存在分子内与分子间质子转移的竞争机制;ABO-H_2O复合物更易出现激发态分子内的质子转移过程.

We investigated the competition mechanism of intramolecular and intermolecular proton transfer of 2-amino-3-(2′-benzoxazolyl)-quinoline-H2O (ABO-H2O) water complex in the excited states by means of the density functional theory and time-dependent density functional theory. The results show that there is an intramolecular hydrogen bond and two intermolecular hydrogen bonds in the ABO-H2O complex. When the complex in the ground state is excited to the first electron excited state, only a 34.157 kJ/mol energy barrier is needed for the ABO-H2O complex to occur intramolecular proton transfer reaction. There is a 63.585 kJ/mol energy barrier in the intermolecular double proton transfer process of the ABO-H 2O complex in the excited state. There is a competitive mechanism for intramolecular and intermolecular proton transfer processes of the ABO-H2O complex in the first electron excited state. The excited state intramolecular proton transfer process is more likely to take place for the ABO-H2O complex.