Univ Cologne Inst Phys Chem Luxemburger Str 116 W-5000 Cologne 41 Germany
Max Planck Inst Festkorperforsch W-7000 Stuttgart 80 Germany

Ba compounds behave very unusual in XPS-studies as they exhibit only small and often negative binding energy shifts. Four different explanations have been given for these observation. To provide a more quantitative basis for these different models and to shed new light on the unusual behaviour of Ba compounds, we calculated total and 1-projected densities of states for Ba metal and three Ba compounds. All four explanations given up to now are not in qualitative agreement with the obtained results. A different possible explanation is discussed.
 

berichte der Bunsen-Gesellschaft für physikalische Chemie, 96 1580-1585, 1992.