Accelerated molecular dynamics of infrequent events

Diffusion of molecules in and on solid substrates often occurs as a series of hops between neighboring binding sites, or potential-energy minima. Simu lation of this type of transport with molecular dynamics becomes challengin g because the time between hops often exceeds times that can typically be p robed with this computational technique. In this paper, we discuss a new me thod, which extends the time scale in molecular-dynamics simulations, while retaining nearly precise dynamic detail. A simple two-dimensional model ha s been used to explore the algorithm in detail. We also discuss the extensi on of the method to more complicated system, involving the diffusion of a A g adatom on the AE (001) surface. (C) 1999 Elsevier Science S.A. All rights reserved.