Fig. 3.

(A–C) Free energy $\left(\mathrm{\Delta }G\right)$, enthalpy $\left(\mathrm{\Delta }H\right)$, and entropy $\left(-T\mathrm{\Delta }S\right)$ of moving a solute from bulk water to a given z location for (A) $M^0$ solute and (B) $M^{+}$ and (C) $M^{-}$ ions. (D and E) Simulation snapshots show that the $M^0$ solute is fully dehydrated (D), whereas the $M^{+}$ ion remains partially hydrated (E), deforming the interface when pulled to $z=-1$. (F) The average number, $\langle N\rangle$, of water oxygen centers in the first hydration shell of the ions and of the neutral solute at various z locations. The hydration shell radius is defined by the first minimum in the solute–water radial distribution function in bulk water.