Theoretical Studies of the Aluminum–Water Clusters Al(H2O)n and Their Ions [Al(H2O)n]+

Publisher Website
Google Scholar
Abstract
With the ab initio molecular orbital calculations, the structures of the neutral clusters Al(H2O)n were optimized, and the vertical ionization energy was evaluated. Two types of the stable clusters are found; the one has a structure [Al(H2O)](H2O)n−1 and the other has [Al(H2O)2](H2O)n−2. The former type of the clusters, in which only one water molecule is directly bonded, is more stable than the latter. The calculated ionization energy with the multi-reference configuration interaction is in very good agreement with the experimental energy determined recently by Fuke’s group, only for the series of the former type of clusters. The structures of the [Al(H2O)n]+ were determined, and the incremental stability energy was evaluated. A very stable ring structure is found in [Al(H2O)4]+. The ring structure persists in [Al(H2O)5]+, but only substantial deformation. The extremely stable structure of [Al(H2O)4]+ explains the observed product distribution of the photo-dissociation recently reported by Fuke’s group.