Rb deposition onTiSe2andTiTe2at 100 K and at room temperature studied by photoelectron spectroscopy

Abstract

The adsorption of Rb on $\mathrm{Ti}{\mathrm{Se}}_{2}$ and $\mathrm{Ti}{\mathrm{Te}}_{2}$ at 100 K was studied by high-resolution core level spectroscopy and low energy electron diffraction. At low coverage, Rb formed a dispersed phase, which condensed into a metallic phase as more Rb was deposited. Continued deposition resulted in layer-by-layer growth of Rb, which was particularly conspicuous on $\mathrm{Ti}{\mathrm{Te}}_{2}$. Most of the Rb intercalated rapidly as the samples were allowed to warm up. For $\mathrm{Ti}{\mathrm{Te}}_{2}$, a small amount of intercalated Rb was detected already at 100 K. When room temperature was reached, only a small fraction of Rb remained on the surface. Equivalent results were obtained instantly when Rb was deposited at room temperature, and valence band spectra from these samples were in excellent agreement with band structures calculated by the linearized augmented plane wave method.