Significant processes at the surface

In the atomisation reaction, we have a flux of molecules impinging on the surface, generally at a temperature (T ) very much lower than the temperature (T) of the surface, and a flux of atoms and molecules departing from the surface. Before we consider the kinetics for these practical conditions, we will examine the situation for an equilibrium system. 

Imagine an isothermal system, at temperature T, consisting of gaseous molecules and gaseous atoms in equilibrium with one another according to the equation 

For many years, the various workers interested in the atomisation reaction (Roberts and Bryce [9], Miller [10], Laidler [11]) favoured the mechanism 

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