摘要
采用多种密度泛函理论方法(如CAM-B3LYP,M062x和w B97x方法),并辅以极化连续介质模型对叔丁氧基自由基(tBu O·)与一系列胺类、烷烃、醇类和醚类反应物之间氢迁移反应的反应机理进行研究.计算结果表明,这类氢迁移反应主要受熵的控制.通过对液相平动熵和气相平动熵得到的活化自由能数据进行对比,可以看出,使用气相平动熵得出的活化自由能明显偏高于实验测量值,而以液相平动熵计算的反应活化自由能垒与实际结果相近,3种方法对胺类和烷烃类反应物体系得出的结果更可靠,对醇类和醚类反应物体系自由能垒则略低.
The reaction mechanisms of hydrogen abstractions from carbon by the t-butoxyl radical were investigated with several density functional theory（ DFT） methods,such as CAM-B3 LYP,M062x and w B97 x. The results show that most of these reactions are dominated more by entropic than by enthalpic factor. The activation free energy barriers were calculated with both gas-phase translational entropy and solution translational entropy,in which those from ideal gas-phase translational entropy（ output of Gaussian job） were much higher than the experimental estimations. It has been verified that free-energy barriers of amines and hydrocarbons reactions generated from solution translational entropies are close to the experimental measurements,but all these methods predict a little low free-energy barriers for alcohols and ethers reactions.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第10期1954-1960,共7页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21373030)资助~~
