Water exchange dynamics around H3O+ and OH− ions

Abstract

In this letter, we report the first computer simulation of the dynamics of water exchanging between the first and second solvation shells of H3O+. Employing different rate theories for chemical reactions such as the transition state theory, the Grote–Hynes theory, the reactive flux method, and the Impey–Madden–McDonald method, we calculate the solvent exchange rates from molecular dynamics simulations that account for explicit polarization effects. In addition, we also study water exchanges around OH− and find that the corresponding time scale is much smaller than that for H3O+.