Magnetic enhancement in nanoscale CoRh particles

The influence of size reduction on the magnetism of CoRh has been studied on a system of isolated nanometric spherical bimetallic ultrafine particles embedded in a polymer matrix. Pulsed fields up to 30 T were used in order to approach the magnetic saturation ( M(S)). Particles with a mean diameter of 1.65 (+/-0.1) nm display a value of 2.38 micro(B) per CoRh unit strongly enhanced compared to values calculated or measured on a bulk alloy. These results were interpreted as the first evidence of the cooperative role of both alloying and size reduction to the enhancement of M(S) in this system associating a 3d FM metal with a 4d metal.