Structural and chemical effects on EELS L-3,L-2 ionization edges in Ni-based intermetallic compounds - art. no. 184110

EELS L-3.2 ionization edges in several Ni-based intermetallic compounds hav e been studied and interpreted in terms of the distribution of electrons in the valence d bands. It is demonstrated that the integral EELS cross secti ons change only slightly upon the formation of intermetallic compounds and, therefore, the charge transfer between atoms is negligible. On the other h and, changes in the energy loss near edge fine structure (ELNES) of the Ni L-3 edge can be readily detected, indicating an important redistribution of d electrons at the Ni site. Full-potential linearized augmented-plane-wave calculations of the density of states (DOS) and simulations of the Ni L-3 edge EELS profiles show that these changes correspond to a hybridization be tween the Ni d band and d bands of the alloying elements. In contrast, stru ctural transformations in the investigated intermetallic compounds do not s ignificantly affect the ELNES as the typical energy resolution of EELS is n ot sufficient to track the slight difference in the DOS between various str uctural modifications of intermetallic compounds.