93Nb NMR Study of the LiNbO3–LiTaO3 Solid-Solution System

Abstract

The 93Nb nuclear magnetic resonance has been studied in sintered powders of the solid-solution system LiNbO3–LiTaO3. The Nb nuclear quadrupole coupling constant decreases linearly with an increase in LiTaO3 concentration and this behavior agrees with the calculated electric field gradient. A variation of the 93Nb NMR linewidth with composition was observed which can be explained on the basis of a random distribution of electric field gradients across the solid-solution range. The linewidths follow closely the well-known expression for the entropy of a randomly distributed binary solid solution.