N-14, Fe-57 and Y-89 spin-echo NMR experiments have been carried out i
n Y2Fe17Nx, 0 < x < 2.8. It is found that the N distribution in the oc
tahedral sites is not random, and a preferred nitrided (with Y-2N conf
iguration)/unnitrided configuration is present. The change in the Fe h
yperfine field distribution with N content provides evidence that latt
ice expansion plays a major role in the Fe moment enhancement upon nit
rogenation.