HIGH-RESOLUTION NUCLEAR-MAGNETIC-RESONANCE STUDY OF THE MOBILITY IN SOLID CRYOLITE, NA3ALF6, FROM ROOM-TEMPERATURE UP TO 300 DEGREES-C

This work describes the temperature evolution of Al-27, Na-23 and F-19 MAS spectra in solid cryolite (Na3AlF6), from room temperature up to 300 degrees C. The description of ionic mobility in the solid is deriv ed from chemical shifts and line-widths evolution for each nucleus wit h temperature. Exchange two-dimensional experiments on Na-23 directly detect Na mobility and equilibrium constants can be measured.