Theory of Microwave Synthesis

There are two specific mechanisms of interaction between materials and micro-waves (i) dipole interactions and (ii) ionic conduction. Both mechanisms require effective coupling between components of the target material and the rapidly 

This non-equilibrium state which arises due to microwave energy input results in the high instantaneous temperature (Tj) of the molecules. The Tj is not directly measurable and it must be greater than the temperature of bulk system (Tb), so as to satisfy the Arrhenius equation (k = Ae ). Therefore, Tj and not Tb ultimately determine the kinetics of the reaction and this accounts for the faster rate observed in microwave reaction. 

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