Theoretical study on the reaction mechanism of CN radical with ketene  

作　　者：ZHAO LiWei KAN Wei YU HaiTao FU HongGang SUN JiaZhong 

机构地区：[1]School of Chemistry and Materials Science,Heilongjiang University,Harbin 150080,China [2]State Key Laboratory of Theoretical and Computational Chemistry,Institute of Theoretical Chemistry,Jilin University,Changchun 130023,China [3]School of Chemistry and Chemical Engineering,Qiqihar University,Qiqihar 161006,China

出　　处：《Science China Chemistry》2008年第2期101-110,共10页中国科学（化学英文版）

基　　金：the National Natural Science Foundation of China (Grant No. 20301006)

摘　　要：The bimolecular single collision reaction potential energy surface of CN radical with ketene (CH2CO) was investigated by means of B3LYP and QCISD(T) methods. The calculated results indicate that there are three possible channels in the reaction. The first is an attack reaction by the carbon atom of CN at the carbon atom of the methylene of CH2CO to form the intermediate NCCH2CO followed by a rupture reaction of the C-C bond combined with -CO group to the products CH2CN+CO. The second is a direct addition reaction between CN and CH2CO to form the intermediate CH2C(O)CN followed by its isomerization into NCCH2CO via a CN-shift reaction, and subsequently, NCCH2CO dissociates into CH2CN+CO through a CO-loss reaction. The last is a direct hydrogen abstraction reaction of CH2CO by CN radical. Because of the existence of a 15.44 kJ/mol reaction barrier and higher energy of reaction products, the path can be ruled out as an important channel in the reaction kinetics. The present theoretical computation results, which give an available suggestion on the reaction mechanism, are in good agreement with previous experimental studies.The bimolecular single collision reaction potential energy surface of CN radical with ketene (CH2CO) was investigated by means of B3LYP and QCISD(T) methods. The calculated results indicate that there are three possible channels in the reaction. The first is an attack reaction by the carbon atom of CN at the carbon atom of the methylene of CH2CO to form the intermediate NCCH2CO followed by a rupture reaction of the C—C bond combined with —CO group to the products CH2CN+CO. The second is a direct addition reaction between CN and CH2CO to form the intermediate CH2C(O)CN followed by its isomerization into NCCH2CO via a CN-shift reaction, and subsequently, NCCH2CO dissociates into CH2CN+CO through a CO-loss reaction. The last is a direct hydrogen abstraction reaction of CH2CO by CN radical. Because of the existence of a 15.44 kJ/mol reaction barrier and higher energy of reaction products, the path can be ruled out as an important channel in the reaction kinetics. The present theoretical computation results, which give an available suggestion on the reaction mechanism, are in good agreement with previous experimental studies.

关 键 词：KETENE CN RADICAL THEORETICAL computation reaction mechanism 

分 类 号：O643.12[理学—物理化学]