COLLISION-INDUCED SHIFT OF THE IONIZATION CONTINUUM AND INTERACTION POLARIZABILITIES OF RARE-GAS ATOMS

Contributions to the incremental pair polarizability traces of Ne, Ar, Kr and Xe due to the shift of the ionization continua are evaluated u sing the Kramers-Kronig-type integral expression modified to account f or the effect of atomic collisions. Interaction trace functions are co mputed and their shapes explained by the interplay between attractive and repulsive interactions, resulting in the redistribution of the dip ole oscillator strength distribution in the continuum. The effect of t he spin-orbit coupling on the interaction polarizability is demonstrat ed. The calculated second dielectric virial coefficients B-epsilon are in better agreement with the room-temperature experimental data than the results of other recent studies are. The strong temperature depend ence of B-epsilon found in experiments remains unexplained, however.