Nanoparticles of iron and iron oxide have been prepared in a thermal diffusion cloud
chamber using pulsed laser evaporation. SEM/TEM studies of these particles reveal a size
distribution with a mean diameter of about 60 Å. This is consistent with the mean particle
size estimated from the magnetic data. The oxidation levels of these nanoparticles prepared
at different partial oxygen pressures were investigated using FTIR. All the samples are found
to exhibit superparamagnetism with blocking temperatures ranging from 50 K to above room …