Surface magnetism of Pd-Fe fine particles

Magnetization and ac susceptibility measurements of Pd/sub 98.0/Fe/sub 2.0/ fine particles (average radii of 7.6-20.4 nm) gave the evidence of magnetic ordering of the surface layer in fine particle. The magnetic transition temperature of the surface layer in Pd-Fe fine particles was determined to be about 40 K based on the peaks in nonlinear susceptibility, and it slightly decreased with decreasing the particle size. Moreover, the size dependence of saturation magnetization indicates that the surface layer has no saturation magnetization at low temperature.