Intracluster rearrangement of protonated nitric acid: Infrared spectroscopic studies of H+(HNO3)(H2O)n

Abstract
Infrared spectra of clusters of protonated nitric acid and water exhibit a marked change with cluster size, indicating that an intracluster reaction occurs with sufficient solvation. In small clusters, H2O binds to a nitronium ion core, but at a critical cluster size the NO+ 2 reacts. A lower bound of 174 kcal/mol is found for the proton affinity of HNO3.