“The Advances in Chemical Physics” series provides the chemical physics field with a forum for critical, authoritative evaluations of advances in every area of the discipline. This volume explores the following topics: • Thermodynamic Perturbation Theory for Associating Molecules • Path Integrals and Effective Potentials in the Study of Monatomic Fluids at Equilibrium • Sponteneous Symmetry Breaking in Matter Induced by Degeneracies and Pseudogeneracies • Mean-Field Electrostatics Beyond the Point-Charge Description • First Passage Processes in Cellular Biology • Theoretical Modeling of Vibrational Spectra and Proton Tunneling in Hydroen-Bonded Systems