DEUTERON SPIN-DIFFUSION AND SPIN-LATTICE RELAXATION IN AMORPHOUS SOLIDS

The effect of spin diffusion on the decay of longitudinal magnetizatio n in deuterated glassy systems is investigated. The decay of longitudi nal magnetization was measured for different dilutions of amorphous de uterated toluene in protonated toluene. For increasing dilution the ma gnetization was found to decay more slowly, indicating the importance of spin diffusion also in deuteron spin systems. A strong correlation between the apparent width of the distribution of spin lattice relaxat ion times and the absolute value of the average spin lattice relaxatio n time was found. This correlation can be explained in terms of spin d iffusion. A simple model is able to reproduce the main features of the observed phenomena. The initial decay rates are shown to be independe nt of spin diffusion. Conclusions concerning the frequency dependencie s of observed average spin lattice relaxation times and width paramete rs are drawn. (C) 1995 American Institute of Physics.