Observation of electronic spectra of three isomers of 2,6-difluoropyridine-water clusters

Electronic spectra of bare and hydrogen-bonded clusters of 2,6-difluoropyridine with water were observed in a supersonic free jet. The spectra indicate the existence of three isomers for 2,6-difluoropyridine-H2O 1:1 clusters. Ab initio molecular orbital calculations also support this result. The structures of the three clusters have hydrogen bonding between water hydrogen and nitrogen (N-site), water hydrogen and fluorine (F-site), and water oxygen and aromatic hydrogen (H-site). In the ground states of cluster cations, calculations suggest the existence of H-site cluster structure, and experiments also support these results. Following excitation into the D-0 state of the N-site cluster from the S-1 state, the cluster dissociates into bare 2,6-difluoropyridine and water, and the molecular orbital calculation also supports this result.