Thermionic Emission of Free Tantalum Clusters

Abstract

The thermionic emission of electrons is obsd. from hot metal clusters. Ta clusters were exposed to a 10 ns laser pulse, and the delayed emission of electrons from the clusters was recorded as a function of cluster size as well as the time after the excitation. A large yield of Tan2 cluster ions, which were born as late as microseconds after the laser pulse, n detected for n >3. The data are discussed in terms of a simple model based on the Richardson-Dushman equation and compared to the results already obtained for W clusters. [on SciFinder(R)]