Electron spin resonance studies of superoxide ions produced by radiolysis in alcoholic media
Air or oxygen saturated alcohols or aqueous alcohols gave O/sub 2//sup -/ on exposure to /sup 60/Co ..gamma.. rays at 77/sup 0/K. These radicals were characterized by low-field parallel ESR features whose g values were solvent dependent. The shift of g/sub parallel/ from 2.0023 was least for aqueous...
Gespeichert in:
Veröffentlicht in: | J. Phys. Chem.; (United States) 1977-07, Vol.81 (15), p.1502-1504 |
---|---|
Hauptverfasser: | , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | Air or oxygen saturated alcohols or aqueous alcohols gave O/sub 2//sup -/ on exposure to /sup 60/Co ..gamma.. rays at 77/sup 0/K. These radicals were characterized by low-field parallel ESR features whose g values were solvent dependent. The shift of g/sub parallel/ from 2.0023 was least for aqueous methanol and greatest for cyclohexanol. In some cases slight annealing above 77/sup 0/K gave an increase in yield and a small shift in g/sub parallel/ toward 2.0023. Dissolution of NaO/sub 2/ in these solvents gave well-defined spectra of O/sub 2//sup -/ with g/sub parallel/ values identical with the limiting values obtained by radiolysis. On annealing the irradiated glasses the g/sub parallel/ features for O/sub 2//sup -/ decayed simultaneously with the growth of features assigned to HO/sub 2/ (or DO/sub 2/). In some cases RO/sub 2/ radicals were also detected. Since the magnitude of g/sub parallel/ is controlled by the strength and direction of the hydrogen bonds, and since the parent dioxygen molecules are not hydrogen bonded, we conclude that solvation is almost completely developed at 77/sup 0/K in these media within |
---|---|
ISSN: | 0022-3654 1541-5740 |
DOI: | 10.1021/j100530a017 |