Attractive dispersion interaction plays a vital role in hydrophobic solvation or hydrophobic association. The neopentane-water, neopentane-urea, neopentane-TMAO and total interaction energies are estimated and the data are presented in Figure and Figure . Here the numbers of neopentane, urea, water and TMAO molecules are same as in the Table . It is important to mention that the neopentane force field that is used, has zero partial charges on each atom. The interaction energies showed in Figures 9 and 10 are only dispersion interaction energies and the raw data is provided in Table -III (Table -III is given in supplementary material). The total solute-solvent interaction energies follow the order as for the two different force fields of TMAO E(w)> E(w-ta)> E(w-ua) > E(w-ua-ta). It is well established that urea stabilizes hydrophobes via favorable dispersion interactions and that is why the more negative solute-solvent interaction energy is observed in urea-water than that in pure water.