Young Joo Lee^a, R.M.Nieminen^a, Eok-Kyun Lee^b, and Sehun Kim^b

^a Laboratory of Physics, Helsinki University of Technology, P.O. Box 1100, FIN-02015 HUT, Finland
^b Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology, Taejon, Republic of Korea

We have simulated the melting behaviour of metal and non-metal clusters for the size of 12<=n<=34, where n is the number of atoms. We find that the non-monotonic variation of melting temperature with size, the dependence of melting, boiling, and sublimation temperatures on the potentials, the existence of a surface-melted phase, and the absence of a premelting peak in heat capacity curves can be explained by the relative stability of the internal atoms to the surface atoms in the clusters.