EFFECT OF SOLVATION ON CHEMICAL-REACTIONS .1. ADDITION OF A SINGLE WATER MOLECULE TO THE H--]OH-+H-2 REACTION(H2O)

The gas phase chemical reaction, H- + H2O --> H-2 + OH-, and the effec t of an additional water molecule on the reaction, H-(H2O) + H2O --> H -2 + OH-(H2O), have been investigated. The optimal structures and ener gies of the reactants, products, two stable intermediates, and the tra nsition state connecting the two intermediates have been determined. T he additional water molecule does not affect the potential surface con gruently: it destabilizes the H-(H2O) minimum, but stabilizes the H-2. ..OH- minimum and the transition state connecting the two intermediate s. However, it stabilizes the products more than the H-2...OH- minimum . Finally, in line with the reduction in the barrier height, the trans ition state for the H-(H2O) to H-2...OH- isomerization moves further a long the reaction path.