Interactions of deposited Ca with TiSe2 and TiTe2 surfaces

Abstract

The interaction of evaporated Ca with TiSe _2 and TiTe _2 surfaces was studied using photoelectron spectroscopy. The surfaces were held at room temperature, and the measured spectra clearly show that the deposited Ca reacted with the substrates, without formation of any Ca overlayers. For depositions on TiSe _2 corresponding to less than 2 nm of Ca there were indications of an intercalation reaction taking place, with charge transfer to the TiSe _2 layers, but as more Ca was added a layer-breaking reaction dominated. For the case of TiTe _2 only a large Ca deposition was studied, resulting in a layer-breaking reaction very similar to that found on the TiSe _2 surface for similar amounts of deposited Ca.

Keywords

• calcium deposition
• titanium dichalcogenides
• layered materials
• photoelectron spectroscopy