NMR relaxation at pressures up to 7 kbar in the superionic conductor Ag3SBr

Abstract NMR studies of Br and Ag nuclei in the superionic conductor Ag 3 SBr at pressures up to 7 kbar have been performed. The obtained phase diagram shows a linear increase of the β − γ transition temperature with rising pressure. The temperature dependence of the Ag-spin-lattice relaxation at constant pressure is analyzed in terms of two thermally activated contributions related to the Ag-ion diffusional jumps. The extracted activation energies at 1 bar are in agreement with conductivity measurements. Pressure dependent relaxation yield negative activation volumes amounting to (−7.5 ± 1.2) cm 3 /mol at 6 kbar.