Net reactions and thermodynamic quantities are shown in table 3. It should be emphasized that because of the size of the systems used in the models, the thermodynamic quantities listed here do not describe the global thermodynamics of the solution but of the local environment in the vicinity of the reaction zone. The quantities are however useful in comparing the relative favorability of the different molecular configurations where the dimerization reaction is occuring. Note that the free energies indicate that the dimerization reaction (eq A1 in table ) is thermodynamically favored.