Nuclear spin relaxation in glassy ionic conductors
نویسندگان
چکیده
The nuclear spin relaxation behaviour in disordered ionically conducting materials is ascribed to a mechanism based on diffusion-controlled relaxation. In this targetdiffusion model, relaxation is assumed to occur at interstitialcy sites, triggered by the arrival of diffusing ions. The dependence of the spin-lattice relaxation rate on the temperature, Larmor frequency and ionic concentration can all be understood with this model. The results of a nuclear spin-lattice relaxation study of the mixed-alkali effect in glasses can, on this basis, be interpreted in terms of changes in ionic mobility. (l)Permanent address: Department of chemktry, University of Cambridge, Lensfield Road, Cambridge CB2 IEW U.K. Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jp4:1992206 JOURNAL DE PHYSIQUE IV
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