Fig. 3.

Estimates for the excess chemical potential, the open circles are the right-side of Eq. (2). The thin solid line is the result of direct numerical simulation. Notice that the variations of the upper results with n are of the same order-of-magnitude as the transfer free energies discussed below (Fig. 5), and that the circles have diminished variation with n, which follows from Eq. (2). Notice also the wide separation in energy range of these different pieces. Simulation results are from Ref. [27]; the SPC/E water model and the ion parameters of Ref. [30] were used. Coordination-number constraints were explicitly imposed within a Monte Carlo simulation.