Size dependent enhancement of spin and orbital magnetism in CoRh nanoparticles Conference Paper uri icon

abstract

  • The magnetism of CoRh nanoparticles (NPs) is investigated experimentally and theoretically. NPs of about 2 nm diameter have been synthesized by decomposition of organometallic precursors in mild conditions of pressure and temperature, under hydrogen atmosphere and in the presence of a polymer matrix. The magnetic properties are determined by SQUID and X-ray magnetic circular dichroism. All the studied CoRh clusters are magnetic with an average spin moment per atom that is significantly larger than the one of macroscopic crystals or alloys with similar concentrations. The experimental results and the comparison with theory suggest that the most likely chemical arrangement is a Rh core with a Co-rich outer shell and some degree of intermixing at the CoRh interface. A detailed analysis of the theoretical results from a local perspective shows that the spin and orbital moments of the Co and Rh atoms at the interface are largely responsible for the enhancement of the magnetization. © 2007 Materials Research Society.

publication date

  • 2007-01-01