Nonadditivity in the Potential for Pairs of Polyatomic Molecules

The question of additivity for the pair potential between collections of harmonic dipole oscillators is examined to the third order of perturbation by the method of Bade. We recover the results of Sparnaay and go on to show that configurations characterized by central symmetry exhibit no net nonadditivity as a result of diple–dipole interactions among the oscillators of each group separately. Suggestions are made concerning the relevance of those results for simple polyatomic molecules and for more general globular systems.