物理化学学报 >> 2007, Vol. 23 >> Issue (06): 916-920.doi: 10.3866/PKU.WHXB20070623

研究论文 上一篇    下一篇

钴原子催化活化乙烷的反应机理

胡启山; 刘俊伶; 李来才; 田安民   

  1. 四川师范大学化学与材料学院, 成都 610066; 四川文理学院化学系, 四川 达州 635000; 四川大学化学学院, 成都 610064

  • 收稿日期:2006-12-05 修回日期:2007-01-02 发布日期:2007-06-04
  • 通讯作者: 李来才 E-mail:lilcmail@163.com

Reaction Mechanism of the Activation of Ethane via Cobalt AtomCatalysis

HU Qi-Shan; LIU Jun-Ling; LI Lai-Cai; TIAN An-Min   

  1. College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, P. R. China; Department of Chemistry, Sichuan University of Arts and Science, Dazhou 635000, Sichuan Province, P. R. China; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China

  • Received:2006-12-05 Revised:2007-01-02 Published:2007-06-04
  • Contact: LI Lai-Cai E-mail:lilcmail@163.com

摘要:

采用密度泛函理论B3LYP方法分别在两种不同基组水平上, 研究了Co原子催化乙烷反应的反应机理, 优化了反应过程中各反应物、中间体、过渡态和产物的构型, 并在同一水平上计算了反应中各驻点的振动频率, 运用自然键轨道理论(NBO)方法分析了各物质的成键情况和轨道间相互作用. 在两种不同基组水平上研究所得的反应历程及相应的能量变化趋势是一致的, 其活化过程可分为C—C键活化及C—H键活化, 分别释放出CH4和H2, 反应速控步骤的活化能后者较前者低, 因此, C—H键的活化较C—C 键活化容易进行.

关键词: Co, 乙烷, 自然键轨道, 过渡态, 反应机理

Abstract:

The reaction mechanism of the activation of ethane via cobalt atom catalysis was investigated by DFT method at two different basis sets at the temperature of 500 K. The geometries and vibration frequencies of reactants, intermediates, transition states, and products were calculated. In addition, the bonding circumstances and orbital interactions were analyzed by natural bond orbital (NBO). The results of two different levels indicated that themechanism and the corresponding energy changing trend were consistent. The activation process could be divided into C—C bond activation and C—H bond activation, and the C—H bond activation was easier than the C—C bond activation.

Key words: Cobalt, Ethane, Natural bond orbital, Transition state, Reaction mechanism

MSC2000: 

  • O643