In this section, we discuss the solvation structures around neopentane and neopentane cavity molecules in water, 8M urea-water, 4M TMAO-water and water-urea-TMAO mixtures for two different force fields of TMAO namely Garcia and Netz force fields. For the analysis of solvation structure of neopentane and cavity, we use radial distribution function and preferential binding coefficients. We also discuss about hydrophobic solvation and it is analyzed in details by computing the solute-solvent interaction energies and the cavity creation free energies. The neopentane association is also quantified using KBI values in osmolyte solutions.