HP-MS High-Pressure Ion Sources

Historically, the introduction of chemical ionization (Cl) by Munson and Field [164, 165] may be considered as the starting point of MS using high-pressure ion sources. They studied gas-phase ion-molecule reactions between reagent gas ions, generated 

A very similar experimental setup was apphed by the group of Castleman [171, 172] in their gas-phase ion-equihbrium studies iuvolving gas-phase hydration of metal cations like Pb and BP. A thermocouple in the reaction chamber enabled continuous monitoring of the temperature. A gating grid between ion source and reaction chamber allowed more acciuate control of the eneigy of the ions entering the reaction cell. 

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