Magnetic and structural characterization of thiol capped ferromagnetic Ag nanoparticles.

Dodecanethiol capped Ag nanoparticles (NPs) have been independently synthesized by the well-known Brust method under the same physical-chemical conditions. The obtained NP present similar sizes (∼2 nm) but different magnetic behaviors. The extended x-ray absorption fine structure analyses at the K-edge of Ag did not reveal any noticeable structural nor topological differences among the samples. In clear contrast with the structure provided for thiol capped ferromagnetic Au NPs, the analysis also brings out the existence of Ag-S bonds in a diffuse region surrounding a reduced Ag core where the magnetism of the Ag NPs would be located. [ABSTRACT FROM AUTHOR]