NA-23 NMR-STUDIES OF DOPED NASICON SYSTEMS

The positions of sodium ions in two doped nasicon systems were investi gated by using Na-23 solid state NMR techniques. The Na-23 NMR spectra with a characteristic powder pattern of quadrupole interaction in the Na1-xZr2-xNbXP3O12 system indicated that sodium ions occupy Na(1) sit es in the crystal structure. For the Na1+2XZr2-xMgXP3O12 system, excep ting the compound with X = 0.1, Gaussian lineshapes were observed due to the distribution of quadrupole parameters and the occupation of bot h Na(1) and Na(2) sites in the crystal structure. Two sodium sites can be distinguished by applying an inversion-recovery experiment.