Polarizability Change in Liquids Due to Many-Body Interactions

Approximate quantum-mechanical expressions for the change in polarizability due to many-body interactions in spherically symmetric liquids, or dense gases, are derived by a variational form of perturbation theory. These expressions are evaluated using Linder's continuum model for the liquid and Slater-type wavefunctions. It is shown that the change in polarizability is approximately [3gα2/8(ea0)2], where α is the unperturbed polarizability and g is a parameter which depends on the dielectric constant and molar volume of the liquid. The predicted increase in polarizability varies from 0.042% for He to 3.54% for Xe.