Evidence for Rb intercalation in TiTe 2

The electronic structure of the layered compound 1 T -TiTe 2 , before and after deposition of Rb, was studied by angle-resolved photoelectron spectroscopy. Rb 4 p core-level spectra were found to consist of two spin-orbit doublets, of which one could be unambiguously attributed to intercalated Rb. Valence band spectra, which were compared with band structure calculations, provided further support that Rb was intercalated, in conflict with recent claims. Possible explanations of the conflicting results are discussed.