The Rate of Atomic Adsorption and Desorption

The free mobility of an adsorbed molecule increases during desorption. 

The increase is largest for atoms that desorb from an immobile state. 

In general surface diffusion will precede desorption. Two extra degrees 

This section and the following sections will explore the transition-state expressions for the rate constants of surface reactions. We start with the adsorption of atoms. The expression for the rate of adsorption according to hard sphere collision theory was covered. Expression (4.112) will be demonstrated as to how it can be rederived within the transition-state theory. 

Substituting the transition-state expression (4.143) and (4.146) for gives for the rate constant of adsorption 

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