Solid⇌liquid transition in model (HF)nclusters

Abstract

We study the stability, energetics and dynamics of small model hydrogen fluoride clusters (HF) n using isoergic molecular dynamics simulations. The largest Lyapunov exponent is computed over the energy range when the clusters melt, and is found to be more useful in defining the onset of melting than Lindemann's index. We also examine the power spectrum of potential energy fluctuations of clusters in the liquid state, which show 1/f dependence over a smaller frequency range than rare-gas clusters of comparable size.