Elementary steps of a catalytic reaction

During a chemical reaction, chemical bonds between atoms are broken and new bonds are formed. The efficiency of a catalyst consists in its ability to favour the electron transitions which occur when bonds are dissolved and formed. A knowledge of the distribution and concentration of the electrons in the catalyst therefore plays a predominant role in the interpretation of catalytic processes 1 I2). To determine the importance of the surface bonds of a catalyst in the elementary step of a catalytic reaction, we have to change the distribution of the electrons over the quantum states of the bonds at the surface of the solid. The electron distribution must be altered where the reacting atoms may take notice of it, i.e. at the surface where the reaction occurs or very close to it, but not in the bulk. 

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