Nuclear magnetic resonance methods of studying mass transport in solids

Abstract

In a number of solids it is now possible to employ NMR techniques to provide reliable and accurate values of translational diffusion coefficients and to use this information to probe the mechanisms of atomic migration. The NMR methods and the strategies followed in mechanistic studies are described by consideration of three specific types of material: molecular-plastic solids, crystals with the fluorite structure and polymer electrolytes. There have been extensive NMR studies of these systems, which highlight various facets of the techniques in addition to being materials with their own interesting transport properties. Particular attention is given to the encounter model for treating relaxation-time data from crystalline solids, the pulsed field gradient NMR diffusion technique and the use of NMR with other types of measurement as a mechanistic probe.