Electronic structure of an oxygen vacancy in Al2O3 from the results of Ab Initio quantum-chemical calculations and photoluminescence experiments

The electronic structure of an oxygen vacancy in α-Al2O3 and γ-Al2O3 is calculated. The calculation predicts an absorption peak at an energy of 6.4 and 6.3 eV in α-Al2O3 and γ-Al2O3, respectively. The luminescence and luminescence excitation spectra of amorphous Al2O3 are measured using synchrotron radiation. The presence of a luminescence band at 2.9 eV and a peak at 6.2 eV in the luminescence excitation spectrum indicates the presence of oxygen vacancies in amorphous Al2O3.