One-dimensional model for water and aqueous solutions. IV. A study of "hydrophobic interactions"

The solute-solute pair correlation function and the potential of mean force (PMF) between two hard-rod solutes in two solvents are studied in one-dimensional systems. One solvent consists of particles interacting via square well (SW) potential. The second consists of particles interacting via "hydrogen-bond-like" (HB) pair potential. It was found that the first minimum of the solute-solute PMF at infinite dilution in the two solvents grows deeper as we increase the strength of the solvent-solvent interaction. In the SW (but not in the HB) solvent, we found that the range of solute-solute pair correlation is larger at lower temperatures (or at larger ε_BB k_BT). The relevance of this finding to the problem of hydrophobic interactions is discussed.