Correlation between diffusion and entropy Adam-Gibbs

7 Correlation between diffusion and entropy Adam-Gibbs relation 

In liquids, one of the most celebrated equations that connects the microscopic dynamics of molecules with thermodynamics is the Adam-Gibbs relation. This relates the translational diffiisivity of the system to configurational entropy as follows  

Here is the translational diffiisivity. Sc is the configurational entropy, and A and C are temperature-independent constants. This beautiful relation between dynamics and thermodynamics has been used extensively to understand the 

As mentioned earlier, it is difficult to obtain a quantitative measure of entropy. By using the 2PT method (the method will be described later in Chapter 19), one can obtain the entropy of water molecules in both major and minor grooves of DNA. One can also get a measure of the translational diffijsivity of those water molecules from the mean-square displacement or velocity autocorrelation function - all these are fortunately easily available with computer simulations. 

This result provides a strong microscopic basis for the observed spine of hydration along the AT minor grooves as demonstrated earlier by X-ray crystallography. 

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