Band structure of substoichiometric titanium nitrides and carbonitrides: spectroscopical and theoretical investigations

Recently, substoichiometric titanium nitrides TiNx (x = 0.45 and 0.61) and carbonitrides TiC(x)Ny (x = y = 0.35) have been synthesized by multiple-energy ion implantation at the surface of pure titanium. Changes in the binary and ternary alloy electronic properties versus defect impurity and vacancy concentrations have been studied by means of core Ti 2p and valence x-ray photoemission spectra (XPS). Moreover, self-consistent tight-binding linear muffin-tin-orbital calculations with empty spheres in place of the missing nitrogen and/or carbon atoms give, among other information, the total density of occupied states, for comparison with the observed valence XPS value.