Bond-energy decoupling: principle and application to heterogeneous catalysis

Abstract

The chemical bond is a still mysterious force that glues atoms together to form molecules and materials. Unlike conventional electromagnetic interactions, the chemical bond cannot be quantified in strength by any known property of the participating species. Here we report an extraordinary principle that the bond energy (E_AB), a quantitative measure of the bond strength, can be decoupled into two contributions of the participating reactants, with each described by a characteristic complex quantity (): . Such a principle has been verified by more than 300 typical bonds, including covalent bonds in molecules and adsorption bonds on metal surfaces; and it can be applied in a wide range of chemical research. Particularly, the characteristic complex quantity, termed chemical amplitude in the present work, can serve as an accurate and unified descriptor for the chemical reactivity of both molecules and metal surfaces, which greatly benefits the study of heterogeneous catalysis. Our finding has not only enabled a direct and practical evaluation of the bond energy, but also revealed a new aspect of the chemical interaction.