Numerical simulation of the platinum L-III edge white line relative to nanometer scale clusters

From an experimental point of view and more particularly in heterogeneous catalysis, the L-III white line is at the center of electronic charge transfer either between either the nanometer scale metallic particle and the support or between the two metals which are present inside the cluster. In this work, we show that a strong correlation exists between the intensity of the white line and the size of the cluster. Thus, at least two physical phenomenon can affect the intensity of the white line: the size of the cluster, which can be considered as an intrinsic effect (density of state of nanometer scale platinum cluster are far from the bulk one), and a possible charge transfer between the cluster and the support, which can be considered as an extrinsic one. If the first results obtained with the FeFF program are encouraging, it is clear that to go further in the analysis, the detailed geometric configurations present in the cluster surface have to be integrated very precisely in order to obtain quantitative effects that would-be more clearly related to the characteristics of the density of states.