Hot Water from Cold. The Dissociative Recombination of Water Cluster Ions

Dissociative recombination of the Zundel cation D5O2+ almost exclusively produces D + 2 D2O with a maximum kinetic energy release of 5.1 eV. An imaging technique is used to investigate the distribution of the available reaction energy among these products. Analysis shows that as much as 4 eV can be stored internally by the molecular fragments, with a preference for producing highly excited molecular fragments, and that the deuteron shows a nonrandom distribution of kinetic energies. A possible mechanism and the implications for these observations are addressed.