Unoccupied electron states of TiS2 studied by means of polarized x-ray absorption

Using polarized x-ray-absorption spectroscopy along with band-structure and real-space multiple-scattering calculations, we have studied unoccupied states of TiS2. With respect to titanium and sulfur sites, the local angular momentum projections of the density of states are presented for states up to 25 eV above the Fermi level. Good agreement between experiment and theory suggests that quadrupole (1s --> d) transitions in Ti K absorption are negligible compared to dipole(1s --> p) transitions. We have applied a new technique for construction of pseudopotentials adapted to the chemical bond and found that previous calculation of electronic states with energies higher than 10 eV above Fermi level was not correct.