Impurity effect on 14N NQR in Na1−xAgxNO2 mixed crystals

The N-14 nuclear quadrupole resonance of the mixed crystals Na1-xAgxNO2 for the range of 0 less than or equal to x less than or equal to 0.16 was measured at room temperature. The frequency shift of N-14 NQR lines from the pure NaNO2 was not detected within experimental accuracy by introducing AgNO2 into NaNO2. However, an increase of the concentration of AgNO2 causes an increase of the line width and weakening of the line intensity due to an increase in inhomogeneity of the electric field gradient (EFG) at the N-14 nucleus. From the probability that a Na+ ion is replaced by a Ag+ ion, characteristic volumes which measure the spatial range of influence of impurities on the EFG at the N-14 site were determined. This volume contains up to the six nearest neighbour Na+ sites from the resonant nucleus. Copyright (C) 1996 Elsevier Science Ltd