Comparison between X-ray absorption spectroscopy, anomalous wide angle X-ray scattering, anomalous small angle X-ray scattering, and diffraction anomalous fine structure techniques applied to nanometer-scale metallic clusters

The emergence of the synchrotron radiation center in the past decade has resulted in a tremendous development of various techniques. XAS is an efficient tool for describing local organization in materials such as nanometer-scale metallic clusters but is insensitive to polydispersity. Ab initio calculations of the diffraction diagram show clearly that the crystallographic network as well as the distribution of the two metals inside the species can also be found. Near the diffraction peak (0,0,0), information regarding the size distribution and the morphology as well as the distribution of the metals inside the cluster can be obtained through a so-called Debye function analysis. For the DAFS technique, a wedding between diffraction and absorption, ab initio calculations will allow us to underline its advantages and its limitations. Finally, a synthesis of all the information given by these techniques is made in order to define a methodology in the building of a structural model.