Theoretical Study on the Photodegradation Mechanism of Pyrethroid Insecticide Fenvalerate in Water  

作　　者：徐香 李先国 孙书文 褚嘉杰 

机构地区：[1]Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China [2]College of Chemistry and Pharmaceutical Sciences,Qingdao Agricultural University

出　　处：《Chinese Journal of Structural Chemistry》2012年第4期505-512,共8页结构化学（英文）

基　　金：supported by the National Natural Science Foundation of China (Nos.40976041 and 20775074)

摘　　要：The photodegradation mechanism of fenvalerate in water has been investigated by density functional theory（DFT）.The geometries of reactants,transition states,intermediates and products are optimized at the B3LYP/6-31G＊ level.The calculated results indicate that the reaction process mainly includes the nucleophilic attack and the substitution reaction by hydroxyl radical to the carbonyl group.By vibrational frequency analysis and intrinsic reaction coordinate（IRC） method,the transition state and its reaction pathway are confirmed.Moreover,the changes of natural population analysis（NPA）,calculated using the Natural bond orbital（NBO） method,are analyzed along with the degradation reaction which can explain the variation of chemical bonds.Additionally,the solvent effect is also investigated and the results show that the reaction preferably takes place in water.The photodegradation mechanism of fenvalerate in water has been investigated by density functional theory（DFT）.The geometries of reactants,transition states,intermediates and products are optimized at the B3LYP/6-31G＊ level.The calculated results indicate that the reaction process mainly includes the nucleophilic attack and the substitution reaction by hydroxyl radical to the carbonyl group.By vibrational frequency analysis and intrinsic reaction coordinate（IRC） method,the transition state and its reaction pathway are confirmed.Moreover,the changes of natural population analysis（NPA）,calculated using the Natural bond orbital（NBO） method,are analyzed along with the degradation reaction which can explain the variation of chemical bonds.Additionally,the solvent effect is also investigated and the results show that the reaction preferably takes place in water.

关 键 词：pyrethroid insecticides PHOTODEGRADATION density functional theory infrared spectra natural bond orbital analysis 

分 类 号：O621.2[理学—有机化学]