Cluster expansion for ion-dipole systems

The result of Brydges and Federbush [1] is generalized to the case of ion-dipole systems of classical statistical mechanics. We establish more accurate values for the parameters for which there is convergence of the cluster expansions, and we also establish the existence and exponential clustering of the correlation functions for infinite volume. It is established that if the ion concentration is not equal to zero, not only the ion-ion but also the dipole-dipole interactions are screened.