RECOMBINATION OF OPPOSITELY CHARGED AQUEOUS CLUSTER IONS USING ELECTROSTATICALLY MERGED ION-BEAMS

A new method for studying cluster-cluster interactions is introduced w hich involves merging mass-selected beams of oppositely charged cluste r ions with an electrostatic quadrupole deflector. Recombination is mo nitored by measuring the rate of fast neutral production. Relative rat e constants have been measured for the reaction of H3O+(H2O)(n)+OH-(H2 O)(m) as a function of cluster size (m = n = 0-3), which display a pro nounced enhancement with clustering. Relative rate constants have also been measured as a function of center-of-mass collision energy for a heavily clustered reaction (n = 3, m = 3) and a lightly clustered reac tion (n = 1, m = 0) revealing that clustering produces a dramatic chan ge in the reaction mechanism.