Influence of electron-phonon interaction on the photoluminescence of titanium oxide in the near-infrared region

The recombination center Ti$^{+3}$-oxygen vacancy, which plays an important role in photocatalysis processes, was studied. When titanium oxide was excited by a laser with a wavelength of 785 nm, a photoluminescence band was observed with a maximum of 1.236 eV. This band appears after crystallization of an amorphous titanium dioxide film in vacuum at a temperature of 650$^{\circ}$C for 30 min. The shape of the band was studied by the method of moments and the parameters of its electron-phonon interaction were determined: the energy of a purely electronic transition is 1.28 eV, the Huang and Rhys factor is 2, and the heat release is 0.04 eV. These values can be used to calculate the parameters of the kinetic coefficients of electronic transitions in strong electric fields.