| Abstract
| - The molecular mechanism of azomethane decomposition on a clean Pt(111) surface has been studied bymeans of a periodic density functional theory (DFT) approach. Three main elementary steps have beenconsidered, which imply either N−N or C−N scission. The thermodynamic order of stabilities suggests thatthe 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 leadingprecisely to the less stable reaction product. A similar trend is found for the other two explored reactionpathways: the less the stability of the resulting product, the lower the corresponding energy barrier. Therefore,the reaction mechanism is found to obey an anti-Brönsted−Evans−Polanyi relationship. Implications forsurface-catalyzed reactions are discussed.
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