SEARCH Articles Figures Tables Classical and Quantum Mechanics in the Theory of Charged-Particle Stopping Mechanical theory Mechanics Theory Mechanism theory Quantum Mechanical Force Fields from Ab Initio Data The Theory of Energy Derivatives Quantum mechanical theory Quantum mechanical treatment of radiation theory Quantum mechanics theory Quantum mechanics theory of bonding The Future Role of Quantum Mechanics Theory and Experiment Working Together Valency and oxidation numbers a historical sketch of bonding theory prior to quantum mechanics