Dynamics of melting of spherical Yukawa and Coulomb clusters

Abstract

Spherical Yukawa and Coulomb clusters are composed of charged particles interacting via the Yukawa and Coulomb potential and confined by the external potential. Melting transitions of these clusters are analyzed by Monte Carlo (MC) and molecular dynamics (MD) simulations. By MC simulations, it is found that the specific heat of relatively small clusters (100 ⩽ N ⩽ 400) has two peaks. The diffusion analyses by MC and MD simulations and the fluctuation analyses related to the Lindemann criteria indicate that two peaks at lower and higher temperatures reflect the losses in ordering in azimuthal and radial directions, respectively.