FeK pre-edges as revealed by resonant x-ray emission -: art. no. 235107

The pre-edge structures at the Fe K absorption edge in model Fe compounds are investigated by resonant x-ray emission spectroscopy (RXES). We demonstrate that decomposition of the pre-edge into its various components can be derived in a very straightforward way from RXES spectra when measured on a fine energy grid, which leads to two-dimensional mapping of the pre-edge region. Thanks to the sharpening effect of the resonant process, features can be observed with resolution better than the 1s core-hole lifetime. Finally, through dispersion of the RXES features, we show that the pre-edge is dominated by transitions to mainly localized states. We believe that RXES constitutes a technique of choice by which to unveil the electronic properties of transition metal atoms in complex systems, particularly in constrained sample environments.