摘要
本文采用DFT/TD-DFT,讨论了1,3-diphenylurea(DPU1)和-NO_2、-N(CH_3)_2对位取代DPU1(即DPU2)与阴离子间的氢键作用.在基态,-NO_2的引入增强了同侧N-H与阴离子的相互作用,而-N(CH3)2的引入减弱了同侧N-H与阴离子的相互作用.另外,与DPU1氢键络合物相比,-NO2和-N(CH_3)_2的引入使DPU2氢键络合物的吸收光谱发生了明显的红移,HOMO→LUMO伴随着明显的电荷转移.在激发态,DPU1和DPU2中的苯环均沿着C-N键发生扭曲,有利于发生分子内电荷转移.DPU1与F-形成氢键,且在激发态发生了质子转移(ESPT),与AcO-形成了双重的分子间氢键.
The hydrogen bonds interaction between the 1,3-diphenylurea （DPU1）, the NO2 or N（CH3 ）2 displaces DPU1 （DPU2） and anions has been investigated by density functional theory/time-dependent density function theory. In the So states, the interaction between the N-H group and anions is strengthened by introducing the -NO2, in contrary, the introducing -N（CH3）2 weakened the hydrogen bonds between the N-H group and anions. In addition, compared with the DPU1 hydrogen bond com- plexes, the substituent - NO2 and - N（CH3） 2 induced the significant bathochromic shift of the first ab- sorption peaks of the DPU2 hydrogen bond complexes, following the obvious charge transfer of the HO- MO--~LUMO electronic transition. In the first excited singlet state, the phenyl rings of DPU1 and DPU2 are twisted along with the C-N, facilitating the intramolecular charge transfer. The hydrogen bond between the DPU1 and F- facilitates the excited state proton transfer. However, the double inter- molecular hydrogen bonds are formed between DPU1 and AcO-.
出处
《四川大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第5期1099-1106,共8页
Journal of Sichuan University(Natural Science Edition)
基金
内蒙古自治区高等学校科学研究资助项目(NJZY202)
校内青年基金资助项目(BSYKJ2013-26)
关键词
含时密度泛函
分子间作用力
电子转移
电子光谱
Time-dependent density functional theory
Intermolecular forces
Electron transfer
Elec-tron spectroscopy
