TEMPERATURE-DEPENDENCE OF PB-207 MAS SPECTRA OF SOLID LEAD NITRATE - AN ACCURATE, SENSITIVE THERMOMETER FOR VARIABLE-TEMPERATURE MAS

The remarkably sensitive temperature dependence of the (207)pb chemica l shift in magic-angle-spinning (MAS) spectra of lead nitrate provides an excellent method for thermometry in solid-state NMR. The temperatu re dependence is uniform over a range of at least -130 to +150 degrees C, and also the NMR sensitivity and linewidth are very favorable. It is demonstrated that lead nitrate can be used in MAS probes to measure sample temperature changes, temperature gradients, MAS heating effect s, and the dynamics of temperature jumps. (C) 1995 Academic Press, Inc .