Rb intercalation of 1T-TaSe2 studied by photoelectron spectroscopy -: art. no. 125107

The electronic structure of the layered compound 1T-TaSe2, before and after deposition of Rb, was studied by angle-resolved photoelectron spectroscopy. Core level spectra verified that the deposited Rb intercalated, with only small amounts remaining on the surface. Valence band spectra revealed major changes in the electronic structure, but good agreement with calculations was found for the bands of Se 4p character. In contrast, the Ta 5d bands were modified by the presence of a strong charge density wave, which was significantly affected by the Rb intercalation. The intercalation also caused a metal to semiconductor transition, although possibly not completely. The observed changes can be attributed to charge transfer, weakened coupling between the layers and reduced hybridization between Se 4p and Ta 5d states. Comparisons are made with related systems.