The onset of nonrigid dynamics and the melting transition in Ar7

Abstract

We have carried out a molecular dynamics (MD) simulation study of melting of Ar₇. By periodically quenching trajectories, we are also able to follow the path of the cluster through configuration space. This procedure yields information about isomerization rates, isomerization dynamics, and the connectivity of the phase space as a function of energy. New criteria for melting and the coexistence of phases in small clusters are compared with the traditional T(E) curves and rms bond fluctuations available from time averages in MD simulations.