Radiolysis studies on reactive intermediates. Technical progress report, November 1, 1975--November 1, 1976

Abstract

During the past year we have focused on the development of new experimental electron magnetic resonance methods and new theoretical models to study reactive reaction intermediates and on the application of these and other methods to study radical and ionic intermediates produced by high energy radiation. We have continued development of electron spin echo spectrometry for studying molecular orientation around trapped radicals, have suggested a new electron spin-lattice relaxation mechanism applicable to glasses, have shown a correlation between electron spin-lattice relaxation times and trapped radical decay and have shown how electron-electron double resonance measurements of cross relaxation can be analyzed to give radical-radical correlation distances. A new model of electron localization in alkanes has been developed, electron solvation in alcohol-alkane mixtures has been studied theoretically and an improved model of electron solvation times has been formulated. Radical reaction intermediates have been detected and identified by spin trapping in methanol, cyanoalkyl and fluoroalcohol liquids, and by X and Q band ESR in methyltetrahydrofuran glass. In aqueous glasses the electronic structure of O/sup -/ and the first solvation shell geometry of e/sup -//sub t/ have been deduced by /sup 17/O substitution. Electron tunneling as a function of the e/sup -//sub t/ energy state and the photoionization mechanism of indole in solution have been investigated.