Two-state energy model

The thermodynamic amplitude information, measuring the amount of energy moving in and out of the molecules, can be used to evaluate AEP. The kinetic frequency information, if studied as a function of temperature, can be put into the Arrhenius equation to yield the value of the activation energy, AE.  

For a relaxation to be observed, the frequency of the interchange process must be similar to the sound frequency, and, in addition, the energies involved in the process must be comparable to the energies available in the temperature variation of the sound wave. Both of these criteria can be met by some of the conformation changes we have been discussing earlier. 

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