Recent Progress in Resonant Soft X-Ray Fluorescence Studies of Molecules

Abstract
A review is presented of some recent advancements in resonant soft X-ray fluorescence spectroscopy applied to molecules. The usefulness of resonant excitation for obtaining site selectivity in studies of the valence band electronic structure of multielement systems is pointed out. The concept of inelastic scattering is discussed for systems with symmetry elements which introduce degeneracy or near-degeneracy of core excited states. The potential of the symmetry selection rules associated with resonant X-ray fluorescence is illustrated in studies of electronic structure as well as molecular dynamics. The use of polarized photons for exciting X-ray emission is discussed, and examples are presented where anisotropy of X-ray emission provides more detailed information. A brief section discusses the experimental considerations relevant for the spectroscopic technique.