Understanding STM images and EELS spectra of oxides with strongly correlated electrons: a comparison of nickel and uranium oxides

Using a theoretical approach combining the local spin density approximation (LSDA) of density functional theory and the Hubbard U term (LSDA + U). we analyse the connection between the experimentally observed electron energy loss spectra and elevated temperature scanning tunnelling images of surface s of semiconducting nickel monoxide NiO and uranium dioxide UO2. We show th at a combination of electron energy loss spectroscopy, atomic-resolution tu nnelling imaging and first principles ab initio calculations provides a pow erful tool for studying electronic and structural properties of surfaces of transition metal and actinide oxides. (C) 2000 Elsevier Science Ltd. All r ights reserved.