Negative ions reactions

Several processes are unique to ions. A common reaction type in which no chemical rearrangement occurs but rather an electron is transferred to a positive ion or from a negative ion is tenued charge transfer or electron transfer. Proton transfer is also conunon in both positive and negative ion reactions. Many proton- and electron-transfer reactions occur at or near the collision rate [72]. A reaction pertaining only to negative ions is associative detaclunent [73, 74],... 

Fehsenfeld, F. C and E. E. Ferguson, Laboratory studies of negative ion reactions with atmospheric trace... 

Fig. 7. Stratospheric negative ion reaction scheme (stages one and two) [after Ref. 13].

Kinetic and thermodynamic data for negative ion reactions involved in stages one and two are to a large extent available from laboratory studies [51]. Stage three data are mostly lacking. 

In 1972 Wentworth, Chen, and Steelhammer set out to write a monograph entitled Negative Ions Reaction and Formation in the Gas Phase, so scientists could plan future research using the ECD. At the time few fundamental properties of thermal electron reactions had been measured. Now many molecular electron affinities and rate constants for thermal electron attachment have been measured. Currently electron affinities and bond dissociation energies can be verified using theoretical SCF calculations on desktop computers. It is especially timely to review the techniques for studying reactions of thermal electrons with molecules and to evaluate the results. 

Several ion-molecule and ion-clustering reactions involving these molecules have been investigated. Negative-ion reactions involving CO3 (with NO2,"" CO2," H2O," and 802 ) and CO (with and 03 ") have led to, inter alia, the complex C03,H20. Association reactions of CO" (with H2 and q257,258 and of HCO" (with have yielded, inter alia, the complexes... 

Fehsenfeld et al. (11) observed a series of negative ion reactions (Reactions 8-10) which could lead to a reduction in the yield of 03, but these processes are unlikely to be important here since at very low... 

McFarland M, Albritton D L, Fehsenfeld F C, Ferguson E E and Schmeltekopf A L 1973 Flow-drift technique for ion mobility and ion-molecule reaction rate constant measurements. III. Negative ion reactions of 0 + CO, NO, H2, and... 

The remainder of this chapter is devoted to a discussion of some of the results obtained from studies of negative-ion-neutral reactions. No attempt is made to include extensive discussion either of associative detachment processes (see Chapter 8) or of those many negative-ion reactions which have been studied only at relatively high energies, i.e., above a few hundred eV. Two-body rate coefficients here are invariably given in units of cm sec and cross sections in units of cm. Energies refer to kinetic energies of the reactant ion in the laboratory system, unless otherwise stated. 

F. C. Fehsenfeld, E. E. Ferguson, and D. K. Bohme, Additional flowing afterglow measurements of negative-ion reactions of D-region interest. Planetary Space Sci. 17, 1759-1762(1969). 

J. F. Paulson, Some negative-ion reactions in simple gases, in Ion-Molecule Reactions in the Gas Phase (Advances in Chemistry Series, No. 58, P. J. Ausloos, ed.), pp. 28-43, American Chemical Society, Washington, D.C. (1966). 

In 1968, Tiernan and co-workers modified the ARL tandem mass spectrometer to permit the investigation of negative-ion reactions. One of these modifications which is largely responsible for successful use of the... 

In addition to identifying and surveying various negative-ion reaction types in the present studies, we have explored isotope and energy effects... 

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