On the Nature of Blue Luminescence in LiF–UO2 Crystals

The spectral characteristics of three types of LiF–UO2 crystals with different concentration of uranium complexes, observable in the IR absorption spectrum at 3574 cm–1, were studied. It was shown that upon excitation into the activator absorption band (λ = 315 nm), luminescence is observed in the blue region of the spectrum (490 nm), caused by charge transfer from the 2p shell of the oxygen ligand, which forms a covalent bond with the hydrogen atom and is part of the hydroxyl ion structure, to the U6+ ion. The emission time was measured at room temperature (750 ns).