STUDY OF NUCLEAR-SPIN RELAXATION IN CLAP GLASSES

F-19 nuclear spin relaxation (NSR) rates are reported at various frequ encies between room temperature and about 800 K, i.e., below and above the glass transition temperature, T-g congruent to 570 K, for glasses of the general composition CdF2-LiF-AlF3-PbF2 (CLAP glasses). The obs erved NSR rate comes from three different contributions. These contrib utions are related to degrees of freedom of the F- ions, and are compa red with conductivity data performed by Moynihan and co-workers on the same glass.