Department of Physics, Agra College Agra U.P India

The electronic, optical, electrical and transport properties of alkali halide crystals have been discussed. The various physical parameters such as ionicity, polarizability, bulk modulus, plasmon energy have been computed and compared with the reported data. A discussion based on PVV theory has been presented for the derived hompolar gap (E_h), Ionic gap (E_c), Perm gap (E_p), average gap (E_g), correlating ionicity with E_c & E_g as well as with various hyperfine interaction. The polarizability is investigated using the Cheml's relation and the investigated values are shown to be in accordance with the values from Clausius-Mossotti relation. The Phillips ionicity is evaluated and is used to determine the bulk modulus of these materials. The Philips ionicity is calculated and compared with the ionicity of the Tubbs and Pauling, models. The plasmon energy is evaluated using the static and optical dielectric. constant using Phillips and perm models.