Z. Karpas et al., ON THE STRUCTURE OF WATER-ALCOHOL AND AMMONIA ALCOHOL PROTONATED CLUSTERS, Journal of the American Society for Mass Spectrometry, 4(6), 1993, pp. 507-512
Collision-induced dissociation (CID) of protonated ammonia-alcohol and
water-alcohol heteroclusters was studied using a triple quadrupole ma
ss spectrometer with a corona discharge atmospheric pressure ionizatio
n source. CID results suggested that the ammonia-alcohol clusters had
NH4+ at the core of the cluster and that hydrogen-bonded alcohol molec
ules solvated this central ion. In contrast, CID results in water-alco
hol clusters showed that water loss was strongly favored over alcohol
loss and that there was a preference for the charge to reside on an al
cohol molecule. The results also indicated that a loose chain of hydro
gen-bonded molecules was formed in the water-alcohol clusters and that
there appeared to be no rigid protonation site or a fixed central ion
.