Hidden states and new peaks in resonant x-ray emission and resonant photoemission

Recent developments in resonant X-ray emision and resonant photoemission are discussed. It will be shown that the scattered X-ray energy and intensity distribution of a resonant X-ray Raman scattering experiment contain the excitation spectrum resulting from a single local spin-flip, a well as dd excitations accompanied by local spin-flip setelites. This phenomenon can be used in experiments to determine the interatomic exchange and superexchange interactions and more generally the local single magnon density of states. Within resonant photoemission, it will be demonstrated that a 'hidden peak' is present in the Auger spectrum of NiO. Proof for the existence of this peak is found in the analysis of the 2p3s3p and 2p3p3p resonant photoemission spectra.