SURFACE AND INTERIOR ANION SOLVATION IN WATER CLUSTERS

We describe the cluster size dependence of the vertical electrostatic stabilization energies E(STAB)(n) of mass-selected I-(H2O)(n) (n = 7-60) clusters in terms of classical electrostatic solvation models for interior solvation, solvation inside the cluster surface and solvation on the cluster surface. Surface anion solvation in clusters of polar and polarizable molecules yields higher vertical electron detachment energies than those for internal anion solvation. The experimental results for E(S)TAB(n) fit somewhat better the model of anion surface solvation and extrapolate well to a value of E(STAB)(infinity) for solvation inside the surface.