X-RAY PHOTOELECTRON, EMISSION, AND ABSORPTION STUDIES OF THE ELECTRONIC-STRUCTURE OF MOLYBDENUM AND TUNGSTEN TRISULFIDES AND THEIR INTERCALATES

The electronic structure of molybdenum and tungsten trisulfides and their lithium intercalates is investigated by X-ray emission, absorption, and photoelectron spectroscopy. The electron density of lithium atoms intercalated into molybdenum and tungsten trisulfides is distributed over both the metal and sulfur atoms, with more over the atoms of the disulfide pair. These compounds are assumed to have an additional donor-acceptor bond involving a lone pair of disulfide sulfur atom electrons and the vacant levels of the metal. A qualitative scheme of the electronic structure of MoS3 is constructed based on experimental results and assuming the presence of a donor-acceptor bond.