To quantify the overall neopentane-neopentane association, we have estimated the Kirkwood Buff integral between neopentane molecules using Eq. 3 in these four different types of solutions. The data are shown in Table . neo-neo association follows the order as: water-urea-TMAO ~ water-Urea> water> water-TMAO for Garcia's TMAO force field. The order is as followed water-urea-TMAO > water-Urea> water ~ water-TMAO. Hence it can be concluded that the hydrophobic association is highest in water-urea-TMAO relative to other three solutions for both the two force-fields of TMAO. On the contrary, it is found by Tah et al. that the population of the extended conformers of a model hydrophobic polymer is enhanced in water-urea-TMAO solution than other three types of solutions. So, the hydrophobic