Electronic structure of disordered titanium monoxide TiO$_y$ depending on stoichiometry

The electronic structure of disordered nonstoichiometric titanium monoxideTiO$_y$ depending on the oxygen content has been studied by the supercell method in the DFT-GGA approximation with the use of pseudo-potentials. An increase in the oxygen content in TiO$_y$ leads to a decrease in the electron density of states near the Fermi level. The calculation of the enthalpy of formation of the ordered and disordered phases has shown that the disordered phase TiO$_y$ is more energetically favorable than the phase without the TiO structural vacancies but is less favorable than the ordered Ti$_5$O$_5$ phase. The stability of the disordered phase increases with the oxygen content.