Using b-hydride elimination to test propositions for characterizing surface catalyzed reactions
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چکیده
We describe the transition states determined using plane wave Density Functional Theory (DFT) for the b-hydride elimination reaction RCH2O(ad)! RCHO(ad) + H(ad) on Cu(111) for R = H, CH3, CH2F, CHF2, and CF3. Our results allow us to assess qualitative descriptions of these transition states based on previous experiments. Our calculations confirm that the character of the transition state is unaffected by fluorine substituents and the transition state for the forward reaction is late. By considering b-hydride elimination from adsorbed methoxy on multiple metal surfaces using DFT, we have examined the hypothesis that surface catalyzed reactions with product-like transition states are more structure sensitive than reactions with reactant-like transition states. 2005 Elsevier B.V. All rights reserved.
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تاریخ انتشار 2016