Transient spectra observed on the pulse radiolysis of aqueous solutions of nitric oxide at p H 7.0 have been assigned to the species NO-, N20,-, and N303-. In acid solution these species are protonated to form the corresponding acids, HNO, HN,Oz, and HN303. Both the basic and acid forms undergo similar reactions, but at different rates, to form the products of radiolysis NzO and NO2-.The basic species decays more slowly than the corresponding acid species but both processes have appreciable activation energies of 15 and 10 kcals/mol, respectively. C o m p~~t e r calculations have been used in conjunction with the experimental data over a wide range of p H and NO concentration to deduce a reaction mechanism consistent with the observed results. Reaction rate constants, acid dissociation constants and extinction coefficients for the v a r i o~~s species are presented and compared with earlier work.Les spectres temporaires observes lors de la radiolyse pulsee de solutions aqueuses d'oxyde nitrique a p H 7.0 ont it6 attribues aux espkes NO-, N 2 0 2 -, et N303-. En solution acide ces espkces sont protonees, en formant les acides correspondants, HNO, HNzOz, et HN303. Les formes acides et basiques subissent toutes les deux des reactions similaires mais a des vitesses differentes, en formant des produits de radiolyse N,O et NO,-.

. Can. 9. Chem. 52.3259(1974). Pulse radiolysis of solutions of alkali metal cations in tetrahydrofuran (THFj demonstrates the formation of solvated electrons e,-, alkali metal cation -ion pairs (M', e,-), and alkali metal anions M -. This paper describes the spectra, extinction coefficients, and radiolytic yields of es-, iithium, sodium, potassium, and cesium species in TFIF. The reaction kinetics are colnplex but largely involve reactions A and B with the concomitant disappearance of all three species by reaction with radiolytically produced radicals. Rate constants and ion-pair dissociation constants for e,-and the sodium and potassium species are presented and compared with data established from studies of blue solutions of alkali metals dissolved in THF. e,-+ M + (M+, e,-)

Flash photolysis of K-, Rb-, and Cs-in tetrahydrofuran (THF) produces the corresponding ion-pairs ( K + , e,-), (Rb+, es-), and (Cs', e,-), followed by the regeneration of the parent metal anion, M u . In mixed-metal solutions containing Na and M where M is K, Rb, or Cs, photolysis of Na-also forms the ( M + , e,-) ion-pair and M-, but with the latter then reforming Na-on an extended time scale. Similar results were obtained in dimethoxyethane (DME) at 213 K, but in this case with the initial formation of a loose ion-pair, (M+, e,-),,,,,.

gated in binary mixtures of THF-ethylamine and ethylamine-ammonia. In each case, a single absorption is observed, which shows a shift in the band maximum to a wavelength intermediate to that obtained in pure solvents. The effects of ammonia on the formation of, and equilibrium between, (M-, es-) and M-in ethylamine are also discussed.

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