Resonant charge-transfer reactions

No observable product was detected from the N02 /N02 reaction at low kinetic energies, placing an upper limit of 10" cm sec on the rate constant for an ion-molecule reaction from this collision. However, the use of isotopically labeled reactants demonstrated that the near-resonant charge-transfer reaction... 

The surface work fiincdon is fonnally defined as the minimum energy needed m order to remove an electron from a solid. It is often described as being the difference in energy between the Fenni level and the vacuum level of a solid. The work ftmction is a sensitive measure of the surface electronic structure, and can be measured in a number of ways, as described in section B 1.26.4. Many processes, such as catalytic surface reactions or resonant charge transfer between ions and surfaces, are critically dependent on the work ftmction. 

Further support for the instability of SiH4+" comes from studies of the charge transfer reactions of a variety of small ions with SiFLt11. Although almost resonant charge transfer was achieved in the reaction of SiHt with Xe+ (AIE = 0.08 0.21 eV), no SiH4+ cations were observed in these guided-ion beam studies. 

Nuclear magnetic resonance (NMR) is a similar type of paramagnetic phenomenon. Like ESR, NMR involves the generation of a signal by the application of an external magnetic field, except that in NMR, shifts in the orientation of the nucleus, rather than of the unpaired electrons, are measured with respect to the external field (cf. Dyer 1965). The major point for our discussion, which would indicate that ESR rather than NMR would function as the modulated carrier-wave, is that unpaired electrons are characteristic of charge-transfer reactions and semiconduction, and as we have seen previously, serotonin and many of its analogs can function as power-... 

Accidental resonant charge transfer is an electron exchange between unlike species also represented by reaction (47), but the energy defect AE is exactly or very close to zero. 

Reactions that are fast at room temperature and do not show a translational energy dependence up to KE n, of a few eV In these cases, large Franck-Condon factors (FCF), i.e., FCF > 10 , usually exist between the ground state of the neutral reactant and its resonant ionic state (resonant with respect to resonant charge transfer). 

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