Mn -doped ZnO , a dilute magnetic semiconductor (DMS), has been prepared in nanocrystalline form by using a soft chemical route. The concurrent diffusional growth of both nanocrystalline Mn -doped ZnO and secondary spinel phase ZnMn2O4 in annealed samples have been studied by using a modified Rietveld method and transmission electron microscope (TEM). Rietveld analysis reveals that both the compounds start growing when Mn concentration is lower and the volume fraction of crystalline spinel phase ZnMn2O4 decreases sharply when Mn concentration increases. TEM study indicates that average particle sizes of both the phases are in nanometer dimensions and are highly crystalline in nature. Magnetization increases initially and then almost saturates with the increase of Mn concentration. The enhanced magnetization could be a combined effect of Mn ions and surface ferromagnetism of nanoparticles.
