ANALYSIS OF ELECTRONIC POLARIZABILITIES IN IONIC-CRYSTALS

The existing sets of additive electronic polarizabilities for alkali halides and alkaline earth chalcogenides are examined by evaluating the high frequency electronic dielectric constants and presenting a comparison with experimental data. The crystalline state values of polarizabilities are also compared with free ion values. Various physical effects responsible for changing the values of polarizabilities in the crystalline state are discussed. The differences in free state and crystalline state polarizabilities are investigated in terms of the classical model due to Havinga and quantum mechanical model due to Yamashita and Kurosawa.