Experimental studies of positive ion chemistry with flow-tube mass spectrometry: birth, evolution, and achievements in the 20th century

Flow-tube mass spectrometry as a technique to measure positive ion–molecule reactions is tracked from its birth to the beginning of the 21st century. Major achievements in the development and the application of this technique are surveyed. The instrumental developments that are considered include advances in ion production and selection, neutral introduction, temperature and energy control in the flow reactor and the detection and probing of product ions and neutrals. Emphasis is given to the use of flow-tube mass spectrometry in measurements of the dependence of ion reactivity on temperature, kinetic energy and internal energy. Achievements in our understanding of basic reaction types are discussed, including electrontransfer, proton-transfer, metal, and organometallic ion reactions and electron–ion recombination. A review is included of fullerene–ion chemistry that has been a focus in the laboratory of the author at York University over the last 10 years. Finally, the progress made in ionospheric and interstellar/circumstellar chemistry, historically the two main areas of application, and the more recent application of flow-tube mass spectrometry in analytical/medical chemistry are highlighted. (Int J Mass Spectrom 200 (2000) 97–136) © 2000 Elsevier Science B.V.