科研之友
微信
新浪微博
Facebook
分享链接
摘要
The molecular mechanism of azomethane decomposition on a clean Pt(111) surface has been studied by means of a periodic density functional theory (DFT) approach. Three main elementary steps have been considered, which imply either N-N or C-N scission. The thermodynamic order of stabilities suggests that the most favored reaction involves N-N scission into two methylnitrene NCH3 adsorbed species. However, it is found that kinetic effects play a crucial role and the most favored reaction appears to be that leading precisely to the less stable reaction product. A similar trend is found for the other two explored reaction pathways: the less the stability of the resulting product, the lower the corresponding energy barrier. Therefore, the reaction mechanism is found to obey an anti-Bronsted-Evans-Polanyi relationship. Implications for surface- catalyzed reactions are discussed.
- 出版日期2008-1-31
