Fig. 3.

Excess chemical potential of a spherical hydrophobic solute as a function of its perpendicular displacement z from the air–water interface. $z\to \infty$ corresponds to bulk vapor, $z\to -\infty$ to bulk liquid, and $z=0$ to the Gibbs dividing surface between the two coexisting phases. Data are shown for atomistic simulations, for the LCW-inspired coarse-grained model of Eq. 5 (with $T>T_{\text{R}}$ parameters $\mathit{ϵ}/T=1.35,$ $\delta =1.84$ Å), and for the estimate in Eq. 10 based on a completely quiescent interface. This solute excludes the center of each water molecule from a sphere of radius $R=5$ Å (as shown in the inset schematic).