Melting of the Au20 gold cluster : does charge matter?

We investigate the dependence upon charge of the heat capacities of the magic gold cluster Au20 obtained from density functional based tight binding theory within parallel tempering molecular dynamics and the multiple histogram method. The melting temperatures, determined from heat capacity curves, are found to be 1102 K for neutral Au20 and only 866 and 826 K for Au{20} cations and anions respectively. The present work proves that a single charge quantitatively affects the thermal properties of the twentymer even for a global property such as melting.