The first peak in the Mechanoluminescence(ML) intensity versus time curve occurs in the deformation region of the crystals which is primarily due to the recombination of dislocation electrons with the V_2-centres. The occurrence of second peak in the post deformation region of the crystals may be understood as follows. In alkali halide crystals there are deep surface states. The absorbed ions, for instance can play the role of such traps. Calculations performed within the model of point ions show that the electron traps on potassium ions absorbed into the KCl (100) perfect surface and near a step are located at 4.27 and 4.01 eV, respectively, from the bottom of the conduction band. Since the dislocation accepter band in the KCl is situated at approximately 2eV below the conduction band bottom, the recombination between deep traps and the electrons carried by dislocation the KCl surface can cause the Auger ionization of other dislocation electrons to the conduction bottom. Thus, if the shallow traps near the conduction band of the crystal may be populated during the process of Auger ionization of the electrons, then the subsequent thermal stimulation may transfer electrons from the shallow traps to the conduction band. Later on the recombination of electrons with V_2-centres in the crystal may give rise to the delayed luminescence where the delay time will depend on the life time of the electrons in the shallow traps. An expression is derived for the time dependence of the ML intensity in colored alkali halide crystals, which suggest that there should be two peaks in the ML intensity versus time curves of the crystals, where one peak should be in the deformation region and the other should be in post deformation region in the crystals. The expression for t_(m1), I_(m1), t_(m2), I_(m2) andI_T are derived.
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