The influence of local chemical composition, structure and surface modifications on the magnetic properties of FexPt1 − x nanoparticles around the equiatomic composition have been studied by means of X-ray absorption spectroscopy (XAS). In particular, the extended X-ray absorption fine structure (EXAFS) and the X-ray magnetic circular dichroism (XMCD) have been employed to investigate the local structure around Fe and Pt atoms and to determine spin and orbital magnetic moments of the two atomic species, respectively. The detailed atomistic picture deduced from these experimental results was compared to recent calculations within the density functional theory that gave the possibility to state design rules for the preparation of nanoparticles with desired magnetic properties. In this paper, a short survey about these findings is given focusing on the experimental work.
Wavelet transform (WT) of extended X-ray absorption fine structure at the Pt L3 absorption edge of FePt nanoparticles in the as-prepared state.