Using the method of secondary ion mass-spectrometry the yield of positive ions from LiF, KCl, KBr has been investigated during the bombardment by electrons and Ar ions with the charge q=1-6 with in the range of energy E=0.02-1 KeV. It has been shown that the increase in q and E of bombarding ions gives the rise in the yield of Li+, K+, F+, Cl+, Br+ and slightly affects the yield of molecular ions (MnXn)+. Inelastic sputtering has its hold on charge and occurs at q> 2. Potential energy of MCI is spent on the formation of neutrals X and double - ionized anions X+. Double - ionized ions M2+ have not been found in the mass-spectra for all the initial values of the charge q. During the electron bombardment of alkali-halide crystals the multiple -charged ions M2+, X2+, M3+, X3+ have been found together with atomic and molecular ions. Their occurrence is connected with the Auger effect as a result of excitation of inner shells of cations and anions.
The rise of the MCI share results in the yield of one-charged ions. From the comparison of ion emission taking place under the action of the both beams, it has been concluded that ionization of the lattice atoms by electrons is more effective than by ions.
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