What NMR has told us about solid acidity

A wide variety of NMR methods are being applied to understand solid acids including zeolites and metal halides. proton NMR is useful for characterizing Bronsted sites in zeolites. Many nuclei are suitable for the study of probe molecules adsorbed directly or formed in situ as either intermediates or products. Adsorbates on metal halide powders display a rich carbenium ion chemistry. The interpretation of NMR experiments on solid acids has been greatly improved by the integration of theoretical chemistry and experiment.