To examine the question whether the harpoon mechanism can account for the reactive behavior of microscopic charged systems, we have investigated the reactivity of coinage metal clusters in gas phase. Our studies reveal that the reactivity between [Cu-8](-)/[Ag-8](-) and chlorine gas is consistent with the harpoon mechanism. An increased reactive cross section is noted through our theoretical estimation based on two methods, ascribed to a long-range transfer of valence electrons from the [Cu-8](-)/[Ag-8](-) cluster to chlorine. Insights into this reactivity will be of interest to other researchers working on obtaining a better understanding of the reaction mechanisms of such superatomic species. (C) 2013 Elsevier B.V. All rights reserved.