High resolution magic angle spinning NMR studies of ³¹P and ¹¹B in fast ion conducting AgI-Ag₂O-P₂O₅ and AgI-Ag₂O-B₂O₃ glasses

Abstract

Silver iodide-based fast ion conducting glasses containing silver phosphate and silver borate have been studied. An attempt is made to identify the interaction between anions by studying the chemical shifts of ³¹P and ¹¹B atoms in high resolution (HR) magic angle spinning (MAS) NMR spectra. Variation in the chemical shifts of ³¹P or ¹¹B has been observed which is attributed to the change in the partial charge on the ³¹P or ¹¹B. This is indicative of the change in the electronegativity of the anion matrix as a whole. This in turn is interpreted as due to significant interaction among anions. The significance of such interaction to the concept of structural unpinning of silver ions in fast ion conducting glasses is discussed.