![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
The narrow components in the 93Nb(I = 9/2) and 45Sc(I = 7/2) NMR spectra of single crystalline PMN and disordered single crystalline PST are due to the 1/2 → -1/2 NMR transition whereas the broad background components are due to satellite transitions.
The macroscopic cubic symmetry is locally broken on the NMR time scale. From the NMR point of view, the structure is homogeneous and there is no need to invoke the existence of “pinned” chemical clusters. The observed NMR spectra in PMN and PST can be described in terms of reorientable dynamic polar nanoclusters-mainly due to Pb2+ site disorder-as invoked by the spherical random bond-random field model.