1 Department of Chemistry and Biochemistry and Centre for Research in Molecular Modeling, Concordia University , Montréal, Québec H4B 1R6, Canada.

Polarizable potential models for the interaction of Li(+), Na(+), K(+), and NH4(+) ions with benzene are parametrized based on ab initio quantum mechanical calculations. The models reproduce the ab initio complexation energies and potential energy surfaces of the cation-p dimers. They also reproduce the cooperative behavior of "stacked", cation-p-p trimers and the anticooperative behavior of "sandwiched", p-cation-p trimers. The NH4(+) model is calibrated to reproduce the energy of the...