Stripping charge

Figure Bl.7.7. Summary of the other collision based experiments possible with magnetic sector instruments (a) collision-mduced dissociation ionization (CIDI) records the CID mass spectrum of the neutral fragments accompanying imimolecular dissociation (b) charge stripping (CS) of the incident ion beam can be observed (c) charge reversal (CR) requires the ESA polarity to be opposite that of the magnet (d) neutiiralization-reionization (NR) probes the stability of transient neutrals fonned when ions are neutralized by collisions in the first collision cell. Neutrals surviving to be collisionally reionized in the second cell are recorded as recovery ions in the NR mass spectrum.

E/2 mass spectrum. Processes of the charge-stripping type ... 

Charge-stripping reaction. An ion/neutral reaction that increases the positive charge on the reactant ion. 

Ionizing collision. An ion/neutral reaction in which an electron or electrons are stripped from the ion and/or the neutral species in the collision. Generally, this term describes collisions of fast-moving ions or atoms with a neutral species in which the neutral species is ionized. Care should be taken to emphasize if charge stripping of the ion has taken place. 

Note It has turned out that medium transmission is optimal for structure elucidation. Too strong reduction of the main beam favors ion losses due to scattering, charge exchange (M -i- N M + IST") or charge stripping processes (M -I- N -> + N" ) instead of delivering additional structural information. 

The protonation of the methyleneiminium cation gives rise to the superelectrophilic methyleniminium dication, 19, which is a gitonic 1,2-dicationic species (carbenium ammonium species). Such a carbodication has been observed by charge stripping mass spectrometry by Schwarz and coworkers.Olah and coworkers have shown by theoretical calculations that the carbenium ammonium species, 19a, is 27.6 kcal/mol more stable than the three-center two-electron (3c-2e) bonded structure, 19b. ... 

Ion suppression in the phase solution plays a predominant role in matrix effects however, the analyte can also be neutralized in the gas phase through neutralization reactions, charge stripping, or charge transfer to another chemical species. 

In a related type of experiment, collisional ionization (or so-called charge stripping) of high-kinetic-energy ions is employed. The major reaction studied is of the general form... 

Schwarz and coworkers258 have been successful in generating the diatomic dication SiF2+ by charge-stripping mass spectrometry (equation 43)259-262. 

Figure 7. Slow scan of the charge-strip-ping region in the MS/MS spectrum of 3-methylindole (upper) and 2-methylindole (lower)...

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