Clustering of water on hydrated protons in a supersonic free jet expansion

Abstract

This paper presents results concerning size distribution and growth in the gas phase of ions in the series H⁺(H₂O)_n. The measurements span a range of cluster sizes up to n =28, a domain not previously investigated quantitatively. The molecular beam sampling technique developed for this study promises to be a powerful tool in the study of ion nucleation phenomenon. Noteworthy observations include the unusual stability of the cluster with n =21 and the absence of trapped molecules of carrier gas within a cluster.