Solvation dynamics in a Brownian dipole lattice: A comparison between theory and computer simulation

Abstract
Papazyan and Maroncelli [J. Chem. Phys. 95, 9219 (1991)] recently reported computer simulations of solvation dynamics of an ion in a Brownian dipole lattice solvent. In the present article we compare these results to predictions of a number of theories of solvation dynamics in the diffusive limit. The frequency‐dependent dielectric response functions needed as input to many of the theories are derived from further simulations of the lattice solvent [H. X. Zhou and B. Bagchi, J. Chem. Phys. 97, 3610 (1992)]. When properly applied, all of the currently popular molecular theories yield reasonable predictions for the time scale of the solvation response. The dynamical MSA model [P. G. Wolynes, J. Chem. Phys. 86, 5133 (1987)] and the memory function theory of Fried and Mukamel [J. Chem. Phys. 93, 932 (1990)] both provide nearly quantitative agreement with all aspects of the solvation dynamics observed in these simulations.