Aggregates of Sn-clusters: partial coalescence during the initial heating

Thermal properties of Sn-clusters with sizes between 3 and 12 nm, prepared by inert gas aggregation, were examined by differential scanning calorimetry (DSC). Besides the expected endothermic fusion effect, which is found to be influenced by the size distribution of clusters in aggregate, an additional thermal effect is detected near the melting point of bulk Sn. It takes place only in the first run of measurements and has exothermic character. We ascribed it to the partial coalescence of clusters.