B. Plastridge et al., THE EFFECT OF CLUSTERING ON MUTUAL NEUTRALIZATION RATES USING ELECTROSTATICALLY MERGED ION-BEAMS - H3O-3)+OH-(H20)(M=0-3)((H2O)(N=0), Journal of physical chemistry, 99(1), 1995, pp. 118-122
Relative rate constants for the mutual neutralization of hydrated hydr
onium and hydrated hydroxide cluster ions have been measured using a n
ew ion optical method which merges mass-selected beams of oppositely c
harged cluster ions with an electrostatic quadrupole deflector. Measur
ements are presented for all combinations of the reaction, H3O+(H2O)(n
=0-3) + OH-(H2O)(m)=(0-3), under one ion optical setting of the intera
ction region (different relative velocities) and a few representative
reactions as a function of relative velocity. A pronounced enhancement
in the relative rate constant is seen with clustering which suggests
that cluster specific rate constants may be required for accurate chem
ical modeling of the D region of the ionosphere. The neutralization re
action mechanism changes dramatically with clustering which is interpr
eted as st change from electron transfer at small cluster size to prot
on transfer with more clustering.