Electronic polarizabilities and dipole moments for alkali halides

An analysis of electronic polarizabilities of ions in alkali halides has been performed by making use of the Wilson–Curtis–Coker model for describing the variation of polarizabilities in going from free state to a bonded state. More accurate values of free state polarizabilities for anions have been obtained making use of photoelastic data. These polarizabilities are found to be larger than Pauling’s values but smaller than Coker’s values. The free state polarizabilities obtained in the present work are then used to estimate the molecular state polarizabilities for 20 alkali halides. The dipole moments and their derivatives with respect to internuclear distances are then calculated and compared with experimental data in order to make a critical test of the polarizability data.