ON THE VALIDITY OF THE INVERTED SNOWBALL PICTURE OF SOLVATION DYNAMICS

In this article we examine the validity of the ''inverted snowball' pi cture of solvation dynamics using results of simulations of an idealiz ed model solvent. The solvent consists of point dipoles which undergo rotational Brownian motion while fixed to the sites of a simple cubic lattice. In this system we observe a much more complex distance depend ence of the solvation response than assumed in the inverted snowball p icture. These results indicate that the intermolecular correlations re sponsible for solvation do not allow for any useful spatial decomposit ion of the response and so point to the inadequacy of such a descripti on for understanding solvation dynamics.