Charge transfer, ionization

Charge-exchange (charge transfer) ionization. Occurs when an ion/atom or ion/molecule reaction takes place in which the chaise on the ion is transferred to the neutral species without any dissociation of either. 

Charge exchange (CE) or charge transfer ionization occurs when an ion-neutral reaction takes place in which the ionic charge is transferred to the neutral. [8] In principle, any of the reagent systems discussed so far is capable to effect CE because the respective reagent molecular ions X" are also present in the plasma ... 

The metal atoms of the neutral metal layers are subject to charge transfer ionization by the principal molecular ions of the ionospheric E-region, NO+ and 02" . The highly stable atomic metal ions are either transported to higher altitudes, where they can undergo electron-ion recombination, or they can be removed by three-body association reactions with atmospheric molecules at lower altitudes, such as N2 ... 

Xie, Y. Hua, L. Hou, K. Chen, R Zhao, W Chen, W Ju, B. Li, H. (2014) Long-Term Real-time Monitoring Catalytic Synthesis of Ammonia in a Microreactor by VUV-Lamp-based Charge-transfer Ionization Time-of-flight Mass Spectrometry. Anal. Chem. 86 7681-7687. 

Some mention should also be made of the inverse of reaction (1.3), leading to ionization. This can be particularly important when charge transfer recombination occurs directly via the ground state of A" (often the case for q = 2 and X = H, He or for q 3 with X = He). Charge transfer ionization turns out to be critical for the fractional abundances of certain ions of Si and Fe (Baliunas and Butler, 1980 Gargaud et al., 1982 Neufeld and Dalgarno, 1987). 

FIGURE 8.6 ASAP MS analysis of a lubricating oil formulation in a methanol atmosphere (b) showing ionization by proton transfer and in a dry nitrogen atmosphere (a) showing charge transfer ionization. 

Type of Cl reaction (PCI), interaction of an ion with an atom or molecule in which the charge on the ion is transferred to the neutral without the dissociation of either charge transfer ionization. 

Macha, S. F McCarley, T. D. Limbach, P. A. Influence of ionization energy on charge-transfer ionization in matrix-assisted laser desorption/ ionization mass spectrometry. Anal. Chim. Acta 1999, 397, 235-245. 

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