2002/07/17 by Juan A. Reyes-Nava, Ignacio L. Garzon, Marcela R. Beltran +1
Physics and Astronomy · #physics.atm-clus #cond-mat.mtrl-sci #physics.chem-ph
published as Revista Mexicana de Fisica 48, 450 (2002). · 10 pages, 4 figures, accepted for publication in Revista Mexicana de Fisica
arxiv created 2002/07/17 · arxiv updated 2009/11/30
Thermal stability properties and the melting-like transition of Nan, n=13-147, clusters are studied through microcanonical molecular dynamics simulations. The metallic bonding in the sodium clusters is mimicked by a many-body Gupta potential based on the second moment approximation of a tight-binding Hamiltonian. The characteristics of the solid-to-liquid transition in the sodium clusters are analyzed by calculating physical quantities like caloric curves, heat capacities, and root-mean-square bond length fluctuations using simulation times of several nanoseconds. Distinct melting mechanisms are obtained for the sodium clusters in the size range investigated. The calculated melting temperatures show an irregular variation with the cluster size, in qualitative agreement with recent experimental results. However, the calculated melting point for the Na55 cluster is about 40 % lower than the experimental value.