Reactivity of Hydrated Hydroxide Anion Clusters with H and Rb: An ab Initio Study

We
present a theoretical investigation of the hydrated hydroxide
anion clusters, OH­(H2O)n–, and of the collisional
complexes, H–OH­(H2O)n– and Rb–OH­(H2O)n– (with n = 1–4).
The MP2 and CCSD­(T) methods are used to calculate interaction energies,
optimized geometries, and vertical detachment energies. Parts of the
potential energy surfaces are explored with a focus on the autodetachment
region. We point out the importance of diffuse functions to correctly
describe the latter. We use our results to discuss the different water
loss and electronic detachment channels, which are the main reaction
routes at room temperature and below. In particular, we have considered
a direct and an indirect process for the electronic detachment, depending
on whether water loss follows or precedes the detachment of the excess
electron. We use our results to discuss the implications for astrochemistry
and hybrid trap experiments in the context of cold chemistry.