[en] The effects of stressed states of crystals in the presence therein of various flaws on electron thermoluminescence and thermoexoemission were studied. Bure LiF crystals and LiF crystals with admixtures of U, Mg, Hg, Fe and In were used in the work. Heat emission spectra are shown for non-deformed and plastically deformed samples. Heat treatment essentially affects the spectral characteristics of heat emission. The admixtures sharply change the character and overall intensity of thermoluminescence and thermoemission spectra. X-ray treatment of pure and admixed LiF crystals also essentially affects those specta. LiF crystal hardening at large irradiation doses gives rise to the assumption that the irradiation hardening is basically caused by formation of vacancies in the bulk of a crystal