System Iw refers to neopentane in water, system IIw-ua refers to neopentane in water-urea, system IIIwtmao refers to neopentane in water-TMAO, and system IVw-ua-tmao refers to neopentane in water-urea-TMAO mixtures. System Cw refers to cavity in water, system Cw-ua refers to cavity in water-urea, system Cw-tmao refers to cavity in water-TMAO, and system Cw-ua-tmao refers to cavity in water-urea-TMAO mixtures. The numbers of cavity, neopentane, water, urea and TMAO molecules are given by Ncavity, Nneo, Nw, Nu and Ntmao respectively (subscripts referring to neopentane cavity, neopentane, water, urea and TMAO). For cavities the C6-term in van der Walls equation is set as zero, only C12 term is present to represent the excluded volume part. The C12 term in cavities is same as the C12 term present in neopentane molecules.