Common features of thermoluminescence in NaCl and LiF crystals

Abstract

We review our work on the thermoluminescent properties of LiF and NaCl crystals. The role of impurities and their effect on glow curves is considered. A spectral analysis of light emitted at glow peaks suggests some common processes active in the two materials, including intrinsic emission from self trapped excitons near 360 nm wavelengths and impurity enhanced emission near 417 nm wavelengths. The latter may be related to the presence of impurity-vacancy dipoles in a form which favors TL emission.

Thermoluminescence in pure LiF crystals: Glow peaks and their connection with color centers

“…Unfortunately such information is not readily available for LiF because optical absorption by halogen interstitials in this material lies in the vacuum ultraviolet spectral region which requires complicated spectroscopic techniques to access. 49 This is the case in the present investigation where the short wavelength cutoff was 400 nm. A more recent discussion, 48 taking into account results of Raman spectroscopy measurements on a range of alkali halides, suggests that the band at 114 nm is due to halogen clusters of the form X3-.…”