XPS INVESTIGATION OF TITANIUM IN MELANITES FROM MONTE VULTURE (ITALY)

X-ray photoelectron spectroscopy (XPS) is used in the present study to investigate the oxidation state and the structural role of titanium i n two melanites with different TiO2 content (similar to 3 % and simila r to 6 % wt) from M.Vulture (Italy). The Ti2p-XPS spectra can be satis factorily fitted when Ti3+ is lodged on octahedral and Ti4+ distribute d over octahedral and tetrahedral sites. The XPS direct estimates of T i site populations match very well with those indirectly obtained from Mossbauer spectroscopy (MS) through the Fe distribution. In addition, good agreement between the Fe2+/Fe3+ ratios estimated by both XPS and MS has been found using Fe3O4 as a standard for interpreting Fe(2)p p hotoelectron spectra.