Argon-methanol clusters

The intensity of the heterocluster ions Ar CHxO+ increased substantially, relative to the neat methanol cluster ions, and the cluster ions of the type Ar (CH3OH) were observed with significant intensity over the entire mass range. At electron energies below the IP of argon—for example, 14.0 eV—the intensity of the unprotonated methanol cluster ions was observed to be greater than that of the pronated cluster ions, as shown in Figure 7-5(b). 

We will now review the studies of intramolecular Penning ionization and multiple scattering/ionization in vdW clusters, followed by our own electron impact studies on argon/methanol heteroclusters. 

Some of the early studies reported abnormal fragmentation patterns when polyatomic molecules were seeded in argon. It was speculated that heteroclusters, such as Ar Xra, are the neutral precursors for the various ions observed in the cluster mass spectrum. Our study of the argon/methanol coexpansions showed that the CMS is definitely affected by the choice of carrier gas, as well as the energy... 

The reactions of small cluster cations of copper and silver, Cu and Ag (n = 1-5), with methanol, ethanol, the two isomers of propanol, and the four isomers of butanol have been studied in a FT-ICR mass spectrometer (200). The ions were produced by FAB and exited through a small hole that aided the clustering process. Once in the cell, the ions were collisionally cooled with argon and allowed to react with the alcohols (3-100 x 10 6 Pa) for periods up to 60 s. The Cu4 ion was produced but was of insufficient abundance for reactivity studies. 

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